How Does Insidious Damage In A Historic Brick Wall Look Like?In an article two weeks ago, we looked at the issues of structural rigidity in a historic brick building. This week we are looking at the same topic but focused on how the small types of deterioration without proper restoration, such as repointing, lead to detrimental failure. We start by looking at the obvious signs of the surface of historic brick masonry, such as biocolonization. Biocolonization, related to historic brick masonry preservation and restoration, refers to the process by which living organisms, such as algae, fungi, lichen, and plants, establish themselves and grow on the surface, and eventually deeper, of historic brick and mortar structures. This colonization can occur due to the porous nature of the historic mortar and brick units and the availability of moisture, especially in older masonry where mortar deterioration or gaps exist. While it might not seem immediately harmful, biocolonization poses a threat destabilization through the the long-term deterioration of the integrity of historic brickwork. The presence of living organisms on historic bricks can lead to several detrimental effects. First, their root systems can penetrate and dislodge the small elements, ay first, of bricks and mortar joints, causing physical damage and compromising structural stability. Second, the biological activity can accelerate the deterioration of mortar, exacerbating the weakening of the masonry. Biocolonization requires careful attention and management in preservation efforts to prevent further decay and structural compromise while preserving the historical and architectural significance of the masonry. The picture below shows an example of a type of publicization on a tree trunk, very similar to the same type of biocolonization or moss / algae growth on a brick wall, together in the collage these images are combined. The brick wall happened to be only a few feet away from the tree. You can see you, because of the shaded area, both mediums, tree bark and historic brick wall, provide an area where algae can grow. The brick wall must be repointed to maintain the building. It is a required part of historic preservation of masonry. ![]() Biocolonization: moss and algae growing on a tree trunk and a nearby masonry wall, in the same way. Unlike the tree though, the brick wall will not regenerate and self-maintain. BiocolonizationBiocolonization can cause slow but critically damaging destruction to historic brick masonry structures. Several causal factors contribute to this phenomenon:
The picture below shows a portion of the base of a brick wall, at a header joint sandwiched between courses of rowlock brick in a common bond historic brick wall. The surface of the wall is covered in a growth of algae which will lead to the growth of moss. This area of the wall, when hydrated or wet from precipitation and rain, stays wet longer than it would if it were not covered with this biological growth. ![]() A common brick in a common bond at a historic brick wall, wet from recent rains, holding moisture longer than it would without algae growth. The next picture below shows an exterior wall, exterior on both sides like a fence between properties. Often exterior walls, exterior on both sides, especially between properties or used like a fence, can be referred to as garden walls or in some cases can be called screen walls or pony walls. Screen walls often have perforation or absences between bricks to allow air or light to pass through. Pony walls will often be short like a kneewall. Unlike a typical kneewall though, pony walls are generally not built to or expected to have a superimposed load. This particular garden wall is built as two separate walls, one on each side of the property line and built double wythe each so in total this would be a quadruple wythe wall. Without a particular coping, over the many decades since the original construction, the mortar and masonry at the top of the historic brick wall has become deteriorated and is now allowing the Virginia Creeper vines to grow into the mortar and exacerbate or accelerate deterioration. The deterioration is not just accelerating but accelerating at an accelerating rate. The difference is that this type of deterioration is nonlinear, it is exponentially increasing. Deterioration of this type should be prioritized for mitigation through repointing and restoration. ![]() Virginia Creeper vines growing over and into the brick and mortar joints as the wall deteriorates slowly, but at an increasing rate.
The next picture below shows a similar wall but with more significant damage. in this case a tree root has grown into the brick and caused the brick to separate and bend out of plane, unlike soft and pliable or flexible materials though, bricks do not actually bend, the mortar joints in this case have become broken and cracked and the brick is dislodged, resulting in overall lateral deflection of the face of the wall. lateral deflection is a serious type of structural masonry failure. once lateral deflection takes place, larger sections of the wall have to be rebuilt or structurally reconfigured You can see signs of the serious damage done to this wall. a stair step crack has formed and the brick has been pushed out of plane, over two inches away from its original vertical shape. the wall is now out of plumb and will continue to deteriorating until a portion of this wall is rebuilt. in most cases, tuck pointing or brick repointing can stop damage or susceptibility of the mortar joints before damage can it be incurred, when conditions of deteriorated are not maintained they can allow areas of historic brick masonry to become significantly deteriorated to the point that more serious damage cannot be easily mitigated. ![]() From this angle, the significant lateral deflection may be indiscernible, but the expanding stair step crack is obvious.
What Leads To BiocolonizationCausal contributing factors can lead to biocolonization in masonry. Some examples follow:
In this photo below, you can see a wet mortar joint during a rainstorm, but this mortar holds and retains moisture at every rain event, every time there’s precipitation. Algae is growing in the recessed mortar joint, as the mortar deteriorates, another acute example where repointing is needed. The next photo shows the same mortar joint from a direct angle. Mitigation and Prevention:To mitigate the slow, damaging effects of biocolonization on historic brick masonry structures, preservation efforts typically include: Gentle Cleaning: Employing cleaning techniques that safely remove biofilms without harming the bricks, such as low-pressure washing or chemical cleaning. This type of approach would often work well where historic mortar is not yet deteriorated. Often though, in modern times, over 100 years after the original construction cleaning without repointing is not actually effective. The picture below shows a historic brick wall with three types of vine leafs growing on the surface of the wall. The vines, in this case, as shown in the photo below have grown into the mortar joints and also into susceptible areas behind the fascia boards and the gutter at the eave of the roof. It is an example of one of the many beautiful properties, built with historic brick, that have been neglected and unmaintained in recent years.
ConclusionIn conclusion, biocolonization poses a genuine threat to the longevity and aesthetics of historic brick masonry structures. Understanding the processes involved and addressing the causal factors are essential steps in preserving these valuable architectural assets. The best approach, in most cases, may be working with a proactive contractor to preserve the masonry of a historic building. Picture below shows a wall with mortar missing at several locations between the historic brick. this wall needs repointing and you can see actual plant growth between some of the mortar joints where stems and leaves are growing from the brickwork to the outside of the building. The next picture below shows a closer view of that wall, but in this picture you can see the Deep recesses clearly. Those recesses are over one inch deep. This wall was originally built with a flush struck mortar joint. The mortar joint originally came out to the edge of the brick. The brick mortar that now remains deep within the recess of the former mortar joints is often also soft and deteriorated, largely just the constituent sand without the line based cementitious binder still intact. These elements of deterioration lead to structural destabilization. In the upcoming week, we will look at additional examples and discuss how repointing, while it seems like a restoration and maintenance type of requirement, can lead to reduction of deterioration and destruction of historic masonry. <p>The post Insidious Damage in a Historic Brick Wall first appeared on Infinity Design Solutions.</p> Via https://www.ids-dmv.com/masonry/insidious-damage-in-a-historic-brick-wall/
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Today we’re taking a look at urban historic brick carriage Houses. The ones that remain today are often built from historic brick masonry. Often they are in rough shape, especially if the historic brick masonry has not been properly repointed over the decades after their original construction. The outline of today’s article follows below:
What is a carriage house?The picture below shows a historic carriage house built over 100 years ago from kiln fired historic brick with lime mortar. Like many surviving carriage houses, this one also happens to be in rough condition. The accessory building has not been properly cared for over the last several decades. The brick has not been pointed, the roof has been poorly maintained, the portals and openings are not even really fully functional, from both an operational and security perspective, at this time. A carriage house is a building originally designed to store horse-drawn carriages and related equipment. They typically have large doors or openings, originally, to accommodate the entry and exit of carriages. Often more modern doors can be custom built into these openings over the more recent decades to allow vehicles to be stored in these spaces as garages. Carriage houses were commonly found in cities like Washington DC during the 18th and 19th centuries when horse-drawn transportation was prevalent. They served as functional structures for storing and maintaining carriages, harnesses, and associated equipment. Over time, many carriage houses have been repurposed for different uses such as garages, storage, or even converted into living spaces. These old buildings are often mistaken for historic garages. Lateral Deflection in Masonry WallsLateral deflection refers to the horizontal movement or displacement that occurs in masonry walls, causing them to lean or bulge. This phenomenon is a concern because it can compromise the stability and structural integrity of the wall. Lateral deflection in masonry walls can occur due to various factors, including:
The picture below shows a angle of the same area of the building shown above, but here you can see the dramatic failure associated with lateral deflection. The wall is literally slowly twisting out of its former vertical plane.
The picture below shows this failing corner from an angle that almost makes it look like a pigeon corner. Originally though when this building was built, this corner was a solid 90° corner with interlocked brick, alternating vertically at each brick from a stretcher and header position. Methods of stabilization and repair for addressing lateral deflection in masonry walls include:
The pictures below shows examples of a type of lateral deflection resistance supports called tiebacks. These particular types of tiebacks are called earthquake washers. They are generally made of cast iron or other types of steel or wrought-iron. The use of this type of lateral deflection resistance systems goes back to the time of original construction of the majority of historic brick buildings in Washington DC’s oldest neighborhoods such as Capitol Hill. A multitude of different shapes of cast iron earthquake washers are relatively common in many of the neighborhoods in Washington DC such as capitol Hill and the Dupont circle area. The picture below has a backwards S type shape. That type of design is actually a little bit less common than some of the other types of designs period one of the most common designs is a star shape come often refer to as a barn star. The next picture below shows one of the most common designs, the barnstar style support element. This shape is relatively common and we’re placed in the middle of the front facade of the building, the support plate is position to provide maximum strength to the facade, to resist lateral deflection. The windows at this particular facade have openings with jack headers, supporting the brick above. 3.Reinforcement: Incorporating steel reinforcement, such as vertical steel beams or reinforcing bars (rebar), into the masonry to increase its tensile strength and resistance to lateral deflection. This type of solution is generally costly in more than one way. The construction cost, to build an elaborate structural system, within an existing building, is prohibitively high. Also though in a non monetary way, building a support system on the interior building like this also effectively leads to a reduction in the available square footage of the space which is problematic in a city like Washington DC where interior space is highly valuable and coveted. 4. Restoration and Repairs: Conducting necessary repairs, including repointing mortar joints, replacing damaged masonry units, or applying protective coatings to prevent further deterioration. Far too often, Routine and corrective maintenance is overlooked or deferred in an effort to save a little bit of money. That small savings can actually result in exponentially increased cost in the long run when the need for routine maintenance goes on attendant and later exacerbates with major failures. It is important to note that stabilization and repair methods will vary significantly depending on the specific condition and configuration of the masonry wall, the extent of lateral deflection. Each problem of this or similar nature requires a customized solution. The stir step crack in the amount of space in the interstitial void created by the separation is significant to the point that it is staggering. The wall and this portion of the building currently creeps closer towards collapse. Here are the next photo below, from a direct position, you can see the massive amount of space between each brick in a stairstep type failure. Unlike the most common typical circumstances where you see a stairstep crack though, this particular condition is related to lateral deflection, not differential settlement. Brick repointing plays a central role in the preservation of historic masonry structures and can help prevent destabilization and lateral deflection. The reasons to consider repounting, quickly and proactively, follow. A. Maintaining Structural Integrity: Over time, the mortar joints in historic masonry structures can deteriorate due to weathering, age, or inadequate original construction. This deterioration weakens the bond between the bricks and can lead to destabilization and lateral movement. Repointing involves removing the deteriorated mortar and replacing it with fresh mortar, restoring the structural integrity of the wall and reducing the risk of lateral deflection. B. Enhancing Load Distribution: Properly repointed mortar joints improve load distribution within the masonry wall. By filling gaps and voids in the joints, repointing helps transfer loads more evenly across the entire wall surface, reducing the localized stress on individual bricks and minimizing the potential for lateral deflection. C. Waterproofing and Moisture Management: Deteriorated mortar joints can allow water infiltration into the masonry wall. Moisture can lead to additional deterioration, including the corrosion of metal reinforcements and freeze-thaw damage. Repointing with an appropriate mortar mix helps restore the wall’s water-resistant properties, preventing moisture penetration and reducing the risk of destabilization due to water-related issues. D. Bonding and Stability: The repointing process involves carefully matching the original mortar’s composition and characteristics to ensure compatibility with the historic masonry materials. The new mortar is applied with proper techniques, creating a strong bond between the bricks and providing stability to the wall. This improved bonding helps resist lateral forces and reduces the likelihood of lateral deflection. E. Preservation of Historic Fabric: Repointing is a preservation technique that respects the historical integrity of masonry structures. It allows for the selective replacement of deteriorated mortar while retaining the original bricks, maintaining the historic appearance and character of the building. By addressing mortar deterioration, repointing helps extend the lifespan of historic masonry structures, preventing further degradation and the associated risks of destabilization and lateral movement. It’s important to note that repointing should be performed by experienced and skilled masons, like IDS, who understand the appropriate techniques, mortar selection, and preservation principles for historic masonry. Proper assessment and planning, in consultation with a qualified and experienced professionals like Infinity Design Solutions can help to ensure the tuckpointing or repointing process is carried out in a manner that considers the mortar and brick characteristics and structural stability of your particular masonry structure. Each building is unique and the structural masonry facets make a difference. Historic masonry upkeep and preservationTo properly maintain, repair, and care for these historic buildings, a knowledge, interest and understanding of historic building principles is required. Here in Washington DC, historic masonry buildings are extremely expensive and the amount of financial loss caused by improper repointing and low quality construction is staggering. However, in addition to the direct financial value of the property, there is also a cultural loss when historic buildings are damaged. By comparison, consider neighboring poor cities, when historic buildings are damaged, it’s not just the loss of value to the property owner, there’s also a loss to all inhabitants and visitors of a city, present and future, who care about architecture, history, and culture. We encourage all of our clients, and all readers of this article and to our blog in general, to prioritize the historic built environment of Washington DC and neighborhoods such as Capitol Hill, Dupont Circle, and Georgetown and become educated on on the difference between proper historic preservation versus improper work which leads to significant damage to the historic fabric of a building. From a conservation and preservation perspective, several approaches can be taken to improve conditions related to deteriorated historic brick masonry. Primarily, lime mortar brick joints and low temperature fired soft red clay bricks should be inspected and checked on a routine maintenance schedule, either seasonally or at least annually. If brick masonry is kept in good condition, the life of embedded wood elements can be significantly extended. Hire a professional contractor which specializes, understands and appreciates historic construction elements and buildings. You can learn a lot more on our blog. Feel free to check it out. If you have questions about the historic masonry of your building in Washington DC, contact us or fill out the webform below and drop us a line. We will be in touch if we can help. <p>The post Lateral Deflection in a Historic Carriage House first appeared on Infinity Design Solutions.</p> Via https://www.ids-dmv.com/masonry/lateral-deflection-in-a-historic-carriage-house/ How Historic Brick Forms a Backbone for a StructureIn this article, part of a two-part series, we are starting a discussion and taking a closer look at the concept of structural rigidity in a historic brick wall, details or touching on the following subtopics:
Individual small units built into a cohesive webThe construction of individual small brick units to create a cohesive bond in a larger assembly is a fundamental aspect of brick masonry, crucial for the structural integrity and stability of walls and buildings. These building assemblies work together by structurally interlocking a multitude of small units together, but the overall strength axis lies in that interlock. In brick masonry, each brick is a small, rectangular building block, each individually strong in compressive force resistance, but without any lateral capacity. These individual bricks are placed and aligned to interlock with one another. The key to their structural strength lies in the way they bond together. Bricks are not simply stacked on top of each other; they are staggered horizontally and vertically, creating a pattern that helps distribute loads evenly. In some ways the bond is like a woven tapestry where the contextual positioning of bricks within the bonds ties bricks together across separate wythes. ![]() A triple wythe screen wall separating backyard parking spaces between rowhomes. Unlike typical Capitol Hill rowhomes built only two bricks thick, this wall has no corner at its end to add rigidity and countering or opposing support. The term “wythe” in the context of masonry refers to a single vertical layer of bricks or stones in a wall. It’s essentially a continuous vertical section of a wall that’s one brick or stone thick. The term is often used in construction and architecture to specify different layers or sections within a wall. The word “wythe” itself has an interesting etymology. It comes from the Middle English word “wythe” or “withe,” which means a willow tree or willow branch. In Old English, it was “wīþ,” and in Middle High German, it was “wīde.” The connection between willow branches and wall construction likely lies in the historical use of woven willow branches or wattle as an early form of construction material for walls and fences. Over time, the term “wythe” evolved to describe the individual layers of bricks or stones in a wall, helping builders and engineers specify and communicate the structure of masonry walls more precisely. ![]() This image shows an area where a group of ironspot facade bricks have been damaged and removed at a front facade. The interstitial remaining bricks are a common brick of different color and with greater variation in shape. The gaps or spaces between bricks are filled with mortar, a mixture of binder (generally made from lime and or portland cement), sand, and water. Mortar serves two essential purposes. First, it provides adhesion, acting as a glue that bonds the bricks together. Second, it helps to evenly distribute loads and stresses across the entire wall by filling in the gaps and providing lateral support. The majority of historic bricks used in Washington DC neighborhoods such as Capitol Hill, Georgetown and Dupont Circle or call common bricks. These bricks were mostly used at the rear facade and the side demising walls and footing and foundations of the building. A different type of brick called a pressed brick was used at the exposed portion of many, but not all, front facades. We specifically use the word “exposed” portion, to describe the area where pressed bricks were most commonly used because even in pressed brick walls of double or triple wythe thickness, the internal wall wythes were generally built with common brick. Common brick was much cheaper but had significantly lower consistent in size, shape, straightness, etc. This inconsistency makes the mortar’s job of filling even more important, because that mortar is required to be the buffer, a flexible intermediary, absorbing the physical and spatial variations and discrepancies. Bricklayers have used a variety of bond patterns, for centuries, to achieve structural stability. The most common bond pattern is the “running bond,” where bricks in one course (horizontal row) overlap the bricks in the course below. This overlap ensures that no vertical joints are continuous, directly aligned between separate wythes or courses, throughout the wall, which would weaken the structure. This pattern is also referred to as a “stretcher bond,” where all bricks are oriented with their long sides facing out. This creates a visually appealing, uniform appearance while still maintaining structural stability, but not as string between wythes as other bond patterns. Header Bricks: In addition to the regular bricks (stretchers) that run lengthwise along the wall, header bricks are used in different brick bond configurations. These are placed perpendicular to the wall’s face, typically every few courses. Header bricks contribute to the wall’s strength by tying the two faces (outer and inner) together and preventing them from separating. The cohesive strength between individual bricks is the key to the rigidity of a wall and building and is based both on the bond, and the interaction between the bricks, mortar, and bond pattern creates a cohesive and stable structure. The staggered arrangement of bricks and the bonding provided by arrangement and mortar allow the wall to resist lateral forces (pressure from the sides) effectively. In contract, compressive loads (pushing together) are somewhat not necessarily reliant on bond and mortar, theoretically. Essentially, the Bricks themselves inherently have a compressive strength resistance, but in practice, those bricks are all part of the overall assembly and that motor either becomes a supporting element or a weak link, and when built correctly the mortar and bond become a supportive element. The individual bricks, when properly arranged and bonded, distribute the forces acting on the wall throughout the entire structure. This prevents the wall from collapsing under its weight or external pressures. The bricks work together as a unified system, with each one playing a critical role in maintaining the wall’s shape and integrity. ![]() The front facade in this picture is potentially in big trouble with significant lateral deflection and failing headers at the window and door openings. ![]() This picture includes a few clues that the building was never intended to have an exposed side, it was built next to a pre-existing buikding and relylied in that building to an extent. ![]() Here you can see the mortar joints were never struck or tooled smoth because they were laid against an existing wall, the beam pockets pass all thevway to the outside now as the original neighboring building no longerstands in place to protect the bare wood. In summary, individual small brick units are strategically arranged, interlocked, and bonded with mortar to create a cohesive and stable structure. The way bricks are stacked, combined with the use of various bond patterns and header bricks, ensures that the wall can resist collapse and maintain its shape and form, even while carrying a heavy load for decades, contributing to the overall strength and durability of historic buildings constructed with brick masonry. Corbelled footings before the widespread use of concrete.Corbelled footings in historic brick structures, predating the widespread use of concrete, were a common construction technique employed to provide support and stability to buildings, especially found in DC historic rowhomes. Corbelling is a construction method where successive courses of bricks or stones project slightly beyond the course immediately below or above them. We often see corbelling at the top of facades of historic rowhomes without applied cornices or mansard roofs. In the context of historic brick structures, corbelled footings involved the use of bricks arranged in a stepped or cantilevered manner to form the foundation of a building which spreads out further getting wider as it goes further down. Corbelled footings served the purpose of gradually expanding the footprint at the base, corbelling distributed the vertical loads of the structure over a larger area, reducing the risk of settling or foundation failure. This technique provided compressive load stability to the walls, helping to counteract or resist some of the external forces, ground movements, and effectively reduce the risk of differential settlement. ![]() A corbelled base of an above ground exterior wall built wider towards the bottom, spreading out for increased stability and bearing area, translating to greater strength overall. A contemporary spread footing, a variant of a basic footing, particularly common in cast-in-place concrete footings, creates additional bearing distribution by dispersing the load of a building or structure across a broader expanse of subsoil. A spread footing features a broader base compared to a standard footing. This wider base is purposefully designed to better distribute the weight and loads imposed by the superstructure. In modern construction practices, the application of spread footings is useful to improve structural stability of a building’s mass. The increased width of the footing lessens the risk of uneven settlement or structural tilting, especially when subjected to varying loads or variations in soil characteristics. By extending the load-bearing area and reducing the pressure on the underlying soil, spread footings can improve the overall bearing capacity at a lower proportional expense to commensurate additional footings or additional engineered soils. ![]() In desperate need of repointing or tuckpointing, the wall has open mortar joints, highly susceptible to water entry and experiencing significant biocolonization and plant growth. Historic corbelled footings were typically constructed using the same materials as the rest of the building, such as common bricks, often locally sourced, and almost never the roman brick nor pressed brick found at exposed building facades. The quality of the materials and workmanship wasn’t really considered in the strength or durability of these footings. Essentially, these footings and successive foundations were considered superior to compacted earth and therein considered sufficient. Often damp-proof courses made from slate tile between a selected brick courses a few inches above the earth grade acted like a wicking barrier. Compared to brick, slate stone is considered to be largely impermeable to water and a course of slate tile installed at the top of the foundation will essentially prevent the permeation of water upwards into the upper walls of the building. Even though over a 100 years ago, the modern liquid or roll applied type waterproof and elements that we use today we’re not available or even invented yet at that time, people still understood that moisture could cause significant damage, both to connected framing and other parts of the structural walls and elements of the building above grade. This slate tile worked similarly to how a modern dampproof course would work today. While corbelled footings were an effective method in their time, they had limitations. Over time, they could suffer from deterioration due to moisture infiltration and the lack of waterproofing techniques that modern concrete footings provide. Additionally, they required additional excavation and work in a confined space, making them labor-intensive, especially in masonry applications. With the advent of concrete as a construction material in the late 19th and early 20th centuries, builders transitioned to using concrete footings. Concrete offered improved strength, durability, and resistance to moisture-related issues. This marked the decline of corbelled footings in favor of more modern foundation systems. Lateral deflection failuresLateral deflection in historic brick masonry walls are a common and significant point of failure, often a culmination of deterioration, and can be attributed to a combination of factors. Lateral deflection failures are often seen in masonry walls with a “belly”, an area projecting outward away from the original vertical plane of the building. ![]() Bricks are only about 3.5″ thick, yet this wall leans over 3″ in a belly area. Some areas were repointed, but not enough has been done over the decades. In some cases earthquake washers are used to provide lateral deflection resistance at untierupted flat walls with bays built into the footprint of a facade. Corners, simply by the nature of the turn in the direction of a wall, consume additional materials and significantly more labor in the construction process, yet provide significant resistance to lateral deflection. Essentially, at a corner in a tall vertical wall, resistance and strength are exponentially bolstered, as the corner creates a combined stabilization force. Often through, internal floor plans, and limited site development space simply don’t allow for economical use of facade projections or recesses. Uninterrupted straight walls, without bays or projections are commonly found at side walls at the ends of building rows. Often slow deterioration of the cohesive strength of the mortar in brick and mortar historic walls can lead to weakening of a wall structure. Once weakened through mortar deterioration, the problems of a compromised strength axis can be exacerbated by biocolonization and plant growth, differential settlement, and outside factors of force such as trash trucks in an alley or renovations in neighboring rowhomes. Mortar plays a crucial role in, not just leveling, but also holding the bricks together in a masonry wall. Over time, the mortar can deteriorate due to various factors, including weathering, moisture, and freeze-thaw cycles. As the mortar deteriorates, its cohesive strength diminishes, leading to a weakening of the overall structure. ![]() A closer view of the wall shows even between individual brick units, the shape has deteriorated to the point that bricks are near dislodged. ![]() Unlike other walls shown and discussed above, this particular wall was not built with a corbelled or intentional step away from the vertical plane, instead the deteriorating wall with significant lateral deflection is waffling out of its previous vertical shape. As mortar deteriorates, the deterioration often create gaps and voids within the wall. Biocolonization, which includes the growth of algae, lichens, and fungi, and can eventually leaf to growth of actual plant life can exacerbate the problem. These microorganisms can further deteriorate the mortar and contribute to surface erosion. As these very small forms of biological growth propagate on the surface of deteriorated mortar, they increase the rate of further deterioration. Fungi, often seen growing on deteriorated organic services like fallen trees in the woods, doesn’t actually have roots, but they have a different type of root like structure called mycelium. Tree roots are known to cause significant damage to building materials, we have shown, on our website, several examples where tree roots have literally buckled and lifted up concrete and or heavy masonry sidewalks or patios. Mycelium is actually very strong, but it doesn’t lift massive structures like tree roots because of a different cellular structure, however In engineering circles, mycelium is actually being analyzed and tested for research and development related to the use of this biological material in actual building materials. Plant growth, such as tree roots, can exploit these voids and crevices, exerting lateral pressure on the bricks and weakening the wall’s structural integrity. One if those articles follows at the link below: Tree Trunks and Roots Moving Brick Columns Historic brick masonry buildings, especially rowhomes, may experience ground settlement differentials over time. This means that one section of the building settles more than another. As a result, the entire wall or specific sections of it may tilt or bow laterally. This lateral movement can lead to structural issues, including cracks and displacement of bricks. Differential Settlement, in this case can lead to or cause lateral deflection, but at the core of the issues each condition is a unique circumstance or problem and each of these problems can occur independently. ![]() Lateral deflection failure causing a significant bow in the wall, a serious problem which could have been mitigated be repointing decades ago. External forces from factors like heavy traffic, construction activities in neighboring buildings, or the passage of large vehicles (e.g., trash trucks in tiny alleyways rubbing against historic brick walls on a weekly or bi-weekly basis) in adjacent alleys can impart lateral forces on the walls. These forces can strain the already weakened mortar and gouge away brick facings, leading to accelerated water entry) and exacerbate lateral deflection. To prevent or address lateral deflection failures in historic brick masonry walls, several measures can be taken. To start, brick walls need impermeable copings at the tops of the walls. For example, add a rooftop where brick walls run above the horizontal or low slope surface of the roof, copings must be installed at the top of the brick walls. This requirement applies to retaining walls and screen walls as well. All freestanding masonry walls need copings to keep water from entering the top of the brick walls, especially where the wall have horizontal tops. Commonly, in Washington DC and DC neighborhoods such as Capitol Hill, Dupont Circle, and Georgetown where there are many historical brick rowhomes, the brick rowhomes are often built with the brick wall running above the flat roof surface. In many cases local quality roof contractors will take a shortcut and wrap the top of the brick wall with a modified bitumen or single-ply type membranes. It’s better to run the membrane over the top of the parapet or brick wall than to stop the roof membrane short of the brick wall. However, still, that does not meet the code requirements. Really the best method to cap the tops of brick walls is to install a metal or similar material coping. Without a coping at the top of the wall, the wall top is a horizontal or near horizontal surface that allows water to sit and then slowly infiltrate into the double or multiple wythe brick wall. Those connected layers of bricks can separate or delaminate with exposure to the elements, as mortar and the assembly of masonry materials break down from unmitigated exposure to moisture. Timely repointing with appropriate, historically compatible mortar can address mortar deterioration, filling voids, and strengthening the wall’s cohesion. Regular structural assessments can identify signs of lateral deflection and guide necessary repairs. In conclusion, ensuring proper foundation support and addressing settlement differentials can help maintain wall stability. Lateral deflection failures in historic brick masonry walls result from a combination of factors, primarily mortar deterioration, biocolonization, plant growth, differential settlement, and external forces. To preserve these historic structures, timely maintenance, structural assessments, and preventive measures are essential. <p>The post Structural Rigidity In A Historic Brick Wall first appeared on Infinity Design Solutions.</p> Via https://www.ids-dmv.com/masonry/structural-rigidity-in-a-historic-brick-wall/ This week we looked at five of the most common frequently asked questions (FAQâs) related to historic brick masonry restoration in Washington DC. Those questions and subsequent answers got into discussions on restoration and preservation, repointing and tuckpointing, and the technical areas of best practices of care for historic masonry structures and facades. A link to last weekâs article can be found here. Today we continue that discussion by looking at a new set of 5 of the most common frequently asked questions. Today we will talk about: We start todayâs discussion with FAQ #6 below, where we left off last week:
In the long-term, unmitigated or untreated mortar deterioration will lead to catastrophic failure of a building, eg. collapse. The brick walls of historic row homes in The historic neighborhoods of Washington DC such as Capitol Hill, Georgetown, and Dupont Circle, are structural walls. Unlike interior non-bearing partitions, structural walls support the dead loads and live loads of a building. The dead load of a building is the mass and weight of the building itself, whereas the live load of a building is the weight of furniture, furnishings and the inhabitants or users of a building. While we use the word catastrophic, and this kind of major failure is in fact catastrophic, you can often see obvious signs of failure slowly happening to a building long before a building starts to collapse. In a past article, at the following link,we looked at a collapsed rowhome rear facade: Learning Masonry Structure Anatomy From Old Ruins â Part IIn this fascinating case study, you learn about the foundation and load path of a typical historic brick rowhome and how the economic blight in Americaâs urban centers affected the choices related to mid-century restoration of defunct systems, often rendering fireplaces abandoned and unrepaired, especially after more modern and contemporary HVAC systems became available. The building in the case study was vacant and unprotected for years. Over time the brick mortar joints became neglected and deteriorated to the extent that the walls first experienced lateral deflection. Repointing or tuckpointing and restoration of the historic brick mortar could have reversed the natural effects of aging. Overtime, slowly the damage became worse and worse. Itâs true that masonry deterioration generally happens very slowly, yet the process of deterioration happens at an increasing rate. Deterioration is nonlinear. In other words, while historic brick deteriorates slowly, it happens faster and faster. Erosion begets yet more erosion, for example. Disintegrating mortar leads to yet more disintegration of mortar deeper within a brick wall assembly. The driving force of disintegration, erosion, and deterioration of mortar are the elements of nature and mainly exposure to water and hydration. This damage happens, invariably at mortar joints. Repointing or tuckpointing are the only way to preserve and stop the process of deterioration, but as the damage becomes extensive, it can lead to worse problems. The picture below shows the exterior episode of a structural brick wall in a historic building. The wall went without proper repointing for decades. As water entered and sat within the mortar joints, through the pressures of freeze-thaw cycles, the bricks cracked and spalled. The damage to this particular wall is so extensive that even from a distance, the deterioration is noticeably visible. Brick spalling refers to the gradual deterioration or flaking of the surface layers of brick masonry structures. This phenomenon primarily occurs due to the infiltration of water into the brickâs pores, especiallyin historic brick masonry like that which was commonly used over 100 years ago in Washington DC, followed by cycles of freezing and thawing. When water enters the brick, it expands as it freezes, exerting pressure on the brickâs internal structure. This repeated expansion and contraction stress lead to the disintegration of the brickâs surface layers, resulting in spalling. Additionally, chemical reactions, often the effects of which can be seen in efflorescence, between water and the minerals within the brick can indicate signs of deterioration leading to spalling. Over time, if not addressed, brick spalling can compromise the structural integrity of the masonry and cause significant degradation, making it a concern in the areas of structural failure as a result of a lack building maintenance over a long period of time.
This particular question is complex, but the bottom line is that issues with deterioration at mortar joints over extended periods of time, has explained in the FAQ above, lead to significant damage and even eventual catastrophic failure. Differentiating between a superficial cosmetic issue and a structural problem requiring repointing in historic brick masonry involves a careful assessment of several factors. First, the depth of mortar deterioration must be examined. It helps to engage a professional like Infinity Design Solutions. Superficial cosmetic issues typically manifest as minor mortar wear on the surface, often due to weathering and exposure to the elements. These cosmetic concerns may not affect the structural stability of the masonry, at first. In contrast, structural problems are characterized by deeper mortar deterioration, potentially extending into the the area beyond the surface of the mortar joint. Another aspect to consider is the presence of gaps or voids between bricks. Superficial issues might involve minor gaps or cracks, primarily affecting the mortar jointsâ outer layers. However, structural problems often result in more extensive gaps, voids, or even complete separation between bricks. These gaps can compromise the load-bearing capacity of the wall, making repointing necessary for restoring structural integrity. When the mortarâs integrity is compromised at this level, it can jeopardize the stability of the entire wall. After the mortar joints become destabilized, secondary problems often result in lateral deflection which leads to wall collapse or stair-step cracking which leads to header failure and collapse. In the realm of structural concerns, itâs important to understand that the mortar in historic brick masonry contributes significantly to the wallâs integral strength. Mortar joints distribute loads and provide cohesion between bricks. As erosion or deterioration progresses into the core of these joints, it weakens the overall structure. A skilled assessment, including probing the mortar joints and assessing the extent of wear, can help identify whether the issue is superficial or requires repointing for structural reinforcement. Proper evaluation and timely intervention are essential to maintain the stability of historic brick masonry structures. The picture below shows the front facade of a historic brick building, built over 100 years ago.
The choice of mortar used in repointing is critical in its effect on the longevity of a restored facade, and it involves a somewhat complex interplay of factors. Traditional historic brick mortars, often dating back a century or more, exhibited significant variation in both the types of aggregates and binders used. These historic mortars tend to be softer and more permeable compared to their modern counterparts. The key distinction is in the binder composition of these mortars. Traditional historic mortars often used slaked lime as a primary binder, with aggregate materials like sand and sometimes even crushed shells, foubd in some coastal areas (like the Carolinas with tabby Ruins along the seaside). These ingredients created a mortar that was relatively soft (on a structural engineering scale) and porous, allowing for flexibility and breathability. This was particularly well-suited to the older bricks and masonry materials used in historic buildings. Over time, this type of mortar could accommodate the natural expansion and contraction of bricks, with changes in weather and temperature, preventing damage due to typical shifts. In contrast, modern mortars commonly use Portland cement as the primary binder, resulting in a mortar mix with higher compressive strength and lower permeability. While this might appear to be an improvement in terms of structural resistance, it will invariably cause potentially devastating problems when used on historic brick masonry, in the repointing or tuckpointing process, for example. The rigidity of modern mortars can be mismatched with the relatively softer and more porous historic bricks, leading to unintended consequences. When subjected to structural stresses or environmental changes, these differences in material properties can cause stress points and even damage to the historic masonry. Moreover, modern mortarsâ lower permeability, when used in repointing or tuckpointing, can disrupt the natural breathability of historic walls. Moisture that would have been absorbed and released through the softer, more porous historic mortar can become trapped within the masonry. This can lead to increased risk of freeze-thaw damage, efflorescence, and spalling, all of which can deteriorate the bricksâ appearance and structural integrity. In essence, while modern mortars may offer advantages in terms of strength and longevity, they must be used judiciously in the context of historic brick facades. The choice of mortar type should prioritize compatibility with the existing masonry materials and take into account the buildingâs specific needs. This often involves replicating the historic mortarâs composition and properties, as closely as possible, to ensure the long-term preservation of the facade. In cases where modern mortars are used, careful consideration, and possibly consultation with professionals such as Infinity Design Solutions, is helpful to mitigate potential adverse effects on historic structures. The picture below shows a facade area where a leaking scupper head caused damage to the brick wall for years while the scupper went unrepaired. Later, when repairs were finally made to the brick, to the right side of the scupper in the photo below, the brick was reset in place by an untrained and unskilled worker and a modern mortar was used. Untrained or unskilled workers will often use incompatible mortars because modern mortars are available at local big box stores and compatible historic mortar is not available off the shelf at big box stores. ![]() The picture above shows a front facade of a brick masonry building with a scupper that runs through the wall from the roof.
No, repointing or tuckpointing alone cannot fix problems of brick damage and deterioration such as cracking and spalling. Repointing proactively on a timely schedule can largely prevent this type of damage from occurring, but even after damage within individual brick units happens, even where it cannot yet be seen, it cannot be fixed by simply repointing. The only way to fix that type of damage is to replace the damaged units. As a side note, as we touch one here, damage can happen within the internal parts of individual brick units for a significant amount of time before those brick units even crack and/or spall or fall apart. The internal parts of a brick, once damaged from unmitigated exposure, are damaged permanently, and meanwhile the outer parts of the brick might not show that damage for years or even decades. Pointing and/or repointing or tuckpointing will not fix that damage that has already happened and even after repointing, if repointing is not done on a timely schedule, the damage thatâs already happened In the past can become visually apparent after pointing happens if that repointing doesnât happen proactively and preemptively. The picture below shows a closer view of a different brick wall where pointing has not been managed properly. This wall should have been repointed years prior to now and in the picture below you can see the condition of those open mortar joints where the mortar has deteriorated significantly now today. In the middle of the picture there is a brick that has cracked and spalled.
There are several types of upkeep and maintenance practices that should be followed by homeowners to protect the facade of a building from damage and deterioration. The pictures below show the work of an overzealous house flipper who added three large dormers to an attic space in a conversion to add interior square footage. The dormers did not initially account for an uninterrupted span of a gutter at the gable roof eave. Now the only practical solution is to have four independent gutter and downspout systems. It looks ridiculous, but itâs much better to collect and channel rainwater away from the facade. It was a big oversight, but at least the facade is being protected. The next picture shows the same facade from a different angle and you can see that the original line of roof eave has been interrupted by the new dormers. The following tips can help maintain a building for increased longevity:
The pictures below show an area at a window header, where a gap developed between the brick and the steel lintel after the lintel had oxidized and became dilapidated. This particular still lintel is the structural reinforcement which supports the flat header. This is an example of a very expensive repair that could have simply been avoided by routine maintenance of upkeep.
By following these maintenance practices and staying vigilant, homeowners can extend the life of a professional repointing job, ensuring the continued preservation of their historic brick facade. Regular care helps protect the buildingâs structural integrity and retains its historical character. <p>The post Top Historic Masonry Repointing FAQs â Part II first appeared on Infinity Design Solutions.</p> Via https://www.ids-dmv.com/masonry/top-historic-masonry-repointing-faqs-part-ii/ Today we will discuss some of the top FAQâs for historic brick tuckpointing or repointing for buildings like the historic row homes of Washington, DC Today, we will answer five specific FAQâs focused on the following topics: This week we are covering some of the most common FAQs that we receive from our clients about repointing. You can learn a lot from the discussion that developed around these questions. 1.What is masonry pointing, tuck pointing, or repointing, and why is it crucial for historic row homes in Washington DC?Tuck pointing or repointing is a commonly needed brick or stone masonry restoration process used to preserve and extend the longevity of historic row homes in Washington DC. This detailed process requires the removal of deteriorated or compromised mortar from the joints between bricks or stones at a buildingâs exterior facade. The weathered mortar is then replaced with fresh, compatible mortar that closely adheres to the original mortarâs composition in terms of functional properties or characteristics. Aesthetics like color and mortar texture are also considered, but the number one important factor is the structural aspects of the mortar. Over time, the erosive influence of natural elements, such as precipitation and resultant hydration, and freeze-thaw cycles can significantly weaken the mortar, thereby creating or expanding gaps and cracks that directly compromise the facadeâs overall strength and its ability to withstand the continued ongoing impact of external forces. The picture below shows an example of a wall that was repointed in recent years with fresh mortar. The stone has a higher compressive strength and lower permeability than historic brickwork, but this facade was repointed with a mortar that works in relative compatibility with the stonework. Although this particular wall has been repointed, the work was not done by our company and our company would be remiss to not point out that there are defects in this work. Our company happens to have a high standard of quality control; we would not accept this work as properly complete. In a photo below we show a close up view of the mortar joint and you can see there is a concave nature to this particular joint. The concave nature of this mortar joint is exaggerated and elongated excessively and would not be acceptable in the quality standards of our company. A rake joint is intended to be recessed inside of the outer face of the masonry units of the wall, there is a rake joint at this location but the rake joint does not finish in a close to plumb or vertical position. We consider that unacceptable. However, we are not alone in this technical perspective. The NPS preservation briefs related to historic masonry restorations explain that the more joint applied should be applied in a relatively consistent The NPS preservation briefs related to historic masonry restorations explain that the more joint applied should be applied in a relatively consistent or uniform application when recessed within the joint. A slightly concave or âbucket handleâ is only slightly concave and acceptable by comparison, but we recommend an even less concave flush joint aimiliar to the original installation, in most cases. It should be noted though that even a so called âflush joint is NOT perfectly flush and does have a slight recess. In conclusion, the important takeaway is that tuckpointing or repointing and overall general facade restoration, upkeep, maintenance and management of exterior brick building faces are very important, actually crucial, at this particular time because we are at the end of the first cycle of required pointing in the life period of the Capitol Hill buildings built around the time range between the late 19th century and the early 20th century. Without repointing or tuckpointing and significant restoration at this particular point in time, deterioration will continue but it will continue at an increasing rate. This increasing rate specifically means that as deterioration continues it will get worse and worse in shorter periods of time, at an exponentially increasing rate. 2. How does the local climate in Washington DC affect the need for repointing?The typical winter season freeze-thaw cycles in the Washington DC area can exacerbate issues associated with deteriorating historic masonry. Freeze-thaw cycles happen in more than just the three months of the winter season of the year, between December 21st or 22nd to March 20th or 21st, (the exact time and day of winter solstice and spring equinox vary a bit each year) in fact thereâs generally a range of about 5.75 months per year when freeze-thaw cycles fluctuating between warm temperatures during the day and cold temperatures at night, can affect historic brick masonry, in our area. (This time of potential freezing temperatures is from about October 21st to April 16th in our area, but abnormalities will continue to increase with global warming. Climate change is real and its happening and will continue to get significantly worse for years to come, regardless of the tempting arguments espoused and proliferated by climate change deniers.) These problems associated with freeze-thaw cycles and their deleterious effect on masonry only happen when the masonry is also affected by moisture. The typical concerns about moisture are related to precipitation, either in the form of regular rainfall, or snow, sleep, mist and other types of less typical precipitation. There is another type of moisture, though, which can affect masonry walls, in the form of condensation from temperature differentials between tempered indoor space and hot or cold outdoor space. Altogether then considering these two factors, both precipitation and condensation, thereâs two main types of moisture that typically affect masonry walls. By-and-large, the larger of these two factors is typical precipitation which we are all familiar with, but the way that precipitation affects historic masonry construction and walls may be a bit counterintuitive. We generally think of rain entering the surface of the brick, accumulating in loose or deteriorated more joints and then freezing, causing significant expansive pressures and forces from the change of water from a liquid to solid state. That typical most common type occurrence is definitely problematic, but water can also follow pathways into masonry that are less intuitive. The picture below shows an area of brick and mortar joints with biocolonization or plant growth on the surface of the mortar joint area. The pictures in the collage above shows an area of a brick masonry exterior wall where the historic lime mortar joints have experienced significant damage from exposure to moisture. Not just recently, but ongoingly for years, these particular joints have already degraded substantially and the inner line binder has significantly dissolved away from the aggregate and sand elements of the mortar joint. Where the plant growth occurs on the surface, deeper into the mortar joint there are capillaries, open and/or partially filled with the roots of the biocolonization and or plant growth. Water on the surface then will follow these pathways deeper into the mortar joint in effect increasing continued deterioration at an accelerated rate, in part because there are already plants growing on top of the mortar joints which will lead to increased deeper hydration. Essentially, the exposure to moisture on the outside of the wall has led to more moisture entry, even deeper, into the interior parts of the brick wall. Now that this damage has occurred water will freeze farther into the wall causing damage at an even deeper location and to a greater extent. This illustrates one of the many reasons that itâs important to be engaged in the care of a building and manage the care of the exterior facade of a historic brick building In a prompt and proactive way. 3. How frequently should repointing be performed to ensure the long-lasting preservation of a historic brick facade?The frequency of repointing in the maintenance of a historic brick facade is an important consideration, in understanding the buildingâs requirements for upkeep, maintenance, and preservation. The information provided by various âauthoritiesâ in the industry, varies widely. While there isnât a fixed timeframe for repointing, several factors contribute to determining the appropriate schedule for this needed process. The rate of deterioration in historic brick masonry hinges on various elements, including climate, exposure to moisture, the quality of the original mortar, and the level of maintenance. In regions like Washington DC with fluctuating weather patterns, extreme temperature variations, and high humidity levels, the impact of freeze-thaw cycles and moisture infiltration accelerates the degradation of mortar. This environmental stress highlights the importance of vigilant maintenance to ensure the long-lasting survival of historic brick facades. In general, it is advisable to conduct a thorough assessment of the mortarâs condition at least every 20 to 30 years. But, we actually recommend an annual assessment of exterior facade conditions,inclusive of much more than just the brick and mortar condition. An annual, overall favade conditions survey should include at least the following items:
Its important to consider all of the items above at least on a routine annusk basis; however, the time frame for specifically focusing just on brick and mortar joints can vary based on the several aforementioned factors. Some buildings may necessitate more frequent repointing, particularly if they face elevated levels of exposure to moisture or harsh weather conditions. Conversely, structures with less exposure may have a longer repointing interval, but dont expect less exposure in the Washington DC area, itâs uncommon. Visual cues play a crucial role in determining when repointing is required. Crumbling, cracking, or missing mortar joints, along with noticeable gaps between bricks, are signs of impending structural issues. Once your building has reached this point, that you can see gaps and voids, you should take action. Professional evaluation and expertise are indispensable in determining the appropriate timing for repointing. Engaging a qualified historic preservation specialist or masonry professional is crucial. They can provide an analysis of the buildingâs condition, considering aspects like mortar composition, bonding materials, and the broader context of its architectural significance. A comprehensive understanding of the historic fabric enables the development of a tailored maintenance strategy that aligns with preservation best practices and minimizes unnecessary intervention or deterioration past the point of maintenance optimality. In summary, repointing is not a one-size-fits-all endeavor, and its frequency should be determined on a case-by-case basis. While a general guideline suggests assessing the mortar every few decades, this interval depends on climate, exposure, original mortar quality, and the overall maintenance regimen. Regular inspections and professional consultation remain key to ensuring the structural integrity and historical continuity and competency of the brick facade. By striking the right balance, property owners can contribute to the long-lasting preservation of brick facades in the historic neighborhoods of Washington DC, like Capitol Hill. 4. Can I attempt repointing as a DIY project, or should I engage professionals?Yes, taking on a DIY repointing projects is a worthwhile endeavor for individuals interested in acquiring valuable skills and knowledge in the realm of brick restoration and repointing. At IDS, we wholeheartedly encourage everyone, regardless of experience, age, physical constitution (within reasonable limits), to explore the world of brick restoration and consider tackling such projects. You can keep it small to start and call in help where it is needed, but understand upfront that repointing, especially with historic masonry is not somethingyou can learn overnight, you need deep and extensive learning and study first. An excellent starting point to gather insights and information about brick restoration and repointing can be found on our blog at ids-dmv.com/blog. This comprehensive resource provides a wealth of information, tips, and techniques that can empower individuals to embark on DIY projects with a solid knowledge base. However, itâs important to recognize that all aspects of repointing demand specialized training, certification, and extensive study, particularly pertaining to safety, proper work practices, OSHA requirements, and environmental hazards. Before even starting any DIY work, we strongly advocate for a full commitment to understanding and adhering to safety guidelines, regulations, and recommendations. Prior to even contemplating undertaking actual work, itâs essential to arm oneself with a thorough understanding of safety protocols to ensure a DIY-erâs safety. While DIY repointing projects offer a great opportunity for self-learning and skill acquisition, itâs important to approach them with a responsible and informed perspective. Acquiring the necessary expertise, education, and training before undertaking repointing work ensures a safe and effective execution of the project. Itâs essential to combine enthusiasm with comprehensive preparation and adherence to safety protocols to guarantee a successful and secure DIY project. 5. Are there instances where repointing might not be the best solution for addressing deteriorating mortar?The answer is clearly and simply yes. Yes, itâs true, repointing is not always the solution for all historic masonry restoration or repair situations. There are several other classes and types of deterioration and or needed types of repair that are different and separate and or unrelated to just repointing. Repointing is very important , when the mortar joints between bricks become deteriorated in the natural aging process of masonry buildings, but There are tons of other types of problems that can occur and take place and need upkeep and maintenance related to historic masonry facades and or brick buildings. Cement, concrete, brick work, and masonry and mortar all experience deterioration and aging from exposure to the natural environment and external elements. The image below shows one of the chimneys from another image higher up in this same article, but in this particular case that chimney is compared to another chimney With a similar issue of near complete destabilization and failure. These chimneys are literally close to the point where they are ready to collapse. At the point when they do collapse, there will be significant damage to both the building and significant risk from the perspective of safety. The issue of structural failure at these chimneys originally started as a area of masonry that needed restoration and upkeep through repointing. Repointing could have literally stabilized these brick chimneys. However, at this point in time, the issue is far past the point where repointing alone can be helpful. At this point, that chimneys must be rebuilt. The adjacent image shows an example of a knee wall that has destabilized due to a compromised or insufficient footing underground. (Without excavation, we have no way to determine if the footing has been compromised by other forces such as adjacent excavation separate from its own construction, or if it was built undersized and excessively small. However, even though we donât really know the true answer, chances are very high that the footing was actually built excessively small, undersized. Itâs just an assumption, but based on past similar issues at front and rear porches at DC rowhomes, qe have overwhelmingly found post, puer, and kneewal footings were built unsized compared to modern standards and the needs to the structure.) The footing was either built at an insufficient depth and/or does not have sufficient capacity to support the kneewall. In relation to the adjacent main building facade, there is differential settlement which has caused the kneewall to move out of plane away from the rear facade wall of the main building. Differential settlement, lateral deflection, and header breakdown are types of structural failures. All of these items are at least related to mortar conditions and in some cases casual reactions or effects of unmitigated joint deterioration, in other words a result of not repointing at the needed time. However, repointing alone will not fix all of these issues. If repointing is not done when it is needed, in a reasonable time frame, the unmitigated mortar deterioration can lead to much more extensive issues. Once these more extensive problems take place and damage extends beyond the surface of a brick masonry facade, the problem is exacerbated and requires much more extensive repair, repairs that pointing or repointing or tuckpointing alone cannot fix. Next weekâs coming discussion In the coming week we will examine more details of historic brick masonry restoration and discuss some other interesting FAQâs. Some of those upcoming topics include the following:
To properly maintain, repair, and care for these historic buildings, a knowledge, interest and understanding of historic building principles is required. Here in Washington DC, historic masonry buildings are extremely expensive and the amount of financial loss caused by improper repointing and low quality construction is staggering. However, in addition to the direct financial value of the property, there is also a cultural loss when historic buildings are damaged. By comparison, consider neighboring poor cities, when historic buildings are damaged, itâs not just the loss of value to the property owner, thereâs also a loss to all inhabitants and visitors of a city, present and future, who care about architecture, history, and culture. We encourage all of our clients, and all readers of this article and to our blog in general, to prioritize the historic built environment of Washington DC and neighborhoods such as Capitol Hill, Dupont Circle, and Georgetown and become educated on on the difference between proper historic preservation versus improper work which leads to significant damage to the historic fabric of a building. From a conservation and preservation perspective, several approaches can be taken to improve conditions related to deteriorated historic brick masonry. Primarily, lime mortar brick joints and low temperature fired soft red clay bricks should be inspected and checked on a routine maintenance schedule, either seasonally or at least annually. If brick masonry is kept in good condition, the life of embedded wood elements can be significantly extended. Hire a professional contractor which specializes, understands and appreciates historic construction elements and buildings. You can learn a lot more on our blog. Feel free to check it out. If you have questions about the historic masonry of your building in Washington DC, contact us or fill out the webform below and drop us a line. We will be in touch if we can help. <p>The post Top Historic Masonry Repointing FAQs â Part I first appeared on Infinity Design Solutions.</p> Via https://www.ids-dmv.com/masonry/top-historic-masonry-repointing-faqs-part-i/ This week we picking up and covering the second part of a discussion looking closely at case studies and the principles of masonry foundation decay and deterioration in the presence of excess moisture. The outline for last week’s and this week’s articles follows below, this week we will cover sections IV through V:
We happen to think this week’s discussion is particularly interesting. In the past we’ve discussed the litany of environmental impacts on historic brick buildings, especially in terms of degradation and deterioration, and we’ve also touched on the issues of climate change. However, in this week’s article we talk much more about the areas of ensuing and amplified environmental driven deterioration. This topic is particularly interesting because it’s not something DC and Capitol Hill residents have had to really deal with in the past, but this issue will be an increasing concern in the future. Restoration and overhaul of historic masonryRestoration and overhaul of historic masonry, a complicated and laborious process, is currently extensively needed within Washington DC’s historic neighborhoods like Capitol Hill. As these historic brick rowhomes bear the marks of time and associated deterioration, weathering and wear, a comprehensive restoration process becomes necessary from both a structural and aesthetic perspective. Historic masonry restoration involves a nuanced process of rejuvenating old buildings, particularly their brick and mortar components, in an attempt to preserve their original character. The lion’s share of historic basement restoration in Washington DC involves some degree of repointing and tuckpointing, which entails repairing the joints between bricks. Historically compatible mortars are used, some with a higher lime content for increased flexibility and breathability, and others with lower lime content for reduced compressive strength. It’s not intuitive, especially in the American culture, to selectively choose a building material because it has a lower strength, but the reality is that historic bricks were fired at a relatively low temperature, especially when compared to modern bricks fired by combustion fuels. Since historic bricks were fired at lower temperatures, they have a much lower compressive strength and for the mortar to be compatible, particularly with common brick as opposed to pressed brick, the mortar must actually have a lower compressive strength. The brick composition varies between buildings and even areas within single historic buildings, two categories are found in most often: bricks at the sides and rear of structures are generally common bricks. These bricks were kiln-fired at lower temperatures, resulting in reduced strength but higher absorbency. At some buildings front facades, brick with higher consistency of constituent materials and shape / size, compared to other bricks in a building assembly are referred to as a pressed bricks. Normally pressed bricks will have a very thin motor joint, often referred to as a butter joint. During restoration, the old mortar between the bricks is tediously removed and replaced with fresh mortar that closely physically mirrors the original but has increased homogeneity. Compatibility and breathability with the existing bricks are prioritized to maintain the building’s historic physical properties. In essence, historic masonry restoration is akin to providing a thorough makeover for aged structures, focusing particularly on their brick ajd mortar components. Through tedious repointing and strategic brick replacement, a building can rejuvenated while adhering to its original design and ensuring its structural durability. Bricks used at the below grade foundation portion of the building were generally common bricks, even though common brick has a lower compressive strength resistance, it was still strong enough for the foundation of these historic buildings. It’s actually very rare for a pressed brick to be used at any location in a building except where it’s visually observable from a public area, and generally only where visually observable at the front facade. So, in this case where a common brick is used at a foundation, almost in all cases, that common brick will also be set in a common mortar joint. Common mortar joints included less binder material, essentially, less lime in mortar mix ratio. Effectively, with a common brick joint at a below grade brick assembly, the walls were generally somewhat porous, especially after decades of aging and deterioration. ![]() We looked at another, similiar. picture from this particular building’s basement in the last article. A sump pump has been installed and there are also separate perforated gravity drains as well. Without the waterproofing, even after tuckpointing the brick would still deteriorate at an accelerated rate. The connection between building deterioration and climate change.In all of our discussions on deterioration and entropy in systems related to masonry and really any part of the overall building, there is a recurring underlying theme. All of the forces of deterioration and eventual destruction of buildings are related to nature. The environment outside, essentially everything out there outdoors, is changing. Climate change is real, despite the politicians and supposed pundits on the right and the conspiracy theorists who believe that climate change is a hoax. It’s actually happening and more and more we will continue to feel the effects of climate change, all around us including right here in our lives where climate change accelerates and exacerbates the elements of nature which lead to masonry deterioration. There’s been pretty strong evidence of climate change, destruction of our environment by proliferation of unregulated chemicals and manufacturing, the greenhouse effect, and acid rain, since the 1970s. However concern for the environment has constantly been derided, considered the passion of quacks, to hug a tree and save the planet. Just four years ago, the president of the United States ridiculed and told Greta Thurnberg, a child at the time, to “chill out’ because she cared about climate change. Meanwhile, while the people in power create a smokescreen, destruction to our environment is happening at an alarming rate and we will pay real consequences. We generally think about those consequences in more abstract terms, such as the idea that we’ll be a little less comfortable in the summer and have storms that are a bit more extreme, forcing us to pay higher insurance premiums and deductibles as the insurance industry continues to profit, even under the strain of increased costs related to storm damage. ![]() This picture shows a modern construction, with CMU aka cinder block, in Capitol. The building was recently converted into a condo building. The single wythe cinder block always leaked, during the approximately 7 year life of the building, since there was no waterproofing at the exterior or foundation of the building. These pressures will significantly increase with continued global warming, past a point of ecological destabilization. As the environment continues to destabilize, weather will become more extreme which will lead to the continuation of the deterioration if historic buildings, especially like those in Capitol Hill and the historic neighborhoods of Washington, DC. There is an interconnection between climate change and the condition of our historic buildings in Washington DC. Weather is simply one of the main drivers of deterioration. As weather becomes more extreme, with more precipitation or specifically precipitation thatless predictable or in greater force overall, there will be a corresponding negative effect to the condition and aging or deterioration process of historic masonry. Climate change ushers in a series of environmental shifts, cascading together, including increased rainfall, more frequent and intense storms, and fluctuations in humidity levels. These changes impact the moisture dynamics of masonry structures. As rainwater infiltrates the porous masonry, the freeze-thaw cycles become more pronounced due to temperature fluctuations. This repeated expansion and contraction stress leads to the gradual deterioration of bricks and mortar joints. The increased moisture levels also provide an ideal breeding ground for biological growth such as mold, mildew, and general bioconalization further accelerating masonry decay. The effects of climate change are not limited to moisture intrusion alone. Rising temperatures and increased humidity levels contribute to a phenomenon known as salt weathering. As rainwater infiltrates the masonry, it dissolves soluble salts present in the materials. Upon evaporation, these salts crystallize, exerting pressure on the masonry and causing surface spalling and efflorescence. Additionally, the intensity of solar radiation can lead to color fading and surface degradation of historic materials, altering the visual character of the buildings. The foundation, a critical component of any structure, is particularly susceptible to the impacts of climate change. Increased rainfall and groundwater levels elevate hydrostatic pressure against the foundation walls. This heightened pressure can lead to seepage and water intrusion through cracks and imperfections in the foundation, causing moisture-related issues within the building. As a result, foundation stability may be compromised, necessitating comprehensive repairs and reinforcement to mitigate the risks of structural damage. ![]() When you think of foundations, cement, and mortar, you don’t really think about the interior type of materials which are extremely susceptible to exposure to moisture. This basement, at the time of original construction was unfinished, and stayed that way for over 100 years until the basement was recently underpinned and a new wall layout was built to create an interior living space. In coming decades, there will be an increase in the trend to use every available square foot off an interior space as property prices increase, not just in dollar for dollar terms but also in terms of a proportion of CPI. In the face of these challenges, the preservation and maintenance of historic masonry buildings will eventually evolve to incorporate adaptive strategies that align with the realities of a changing climate. Sustainable preservation practices, such as the application of modern breathable waterproofing systems and protective coatings, offer a means to mitigate certain types of moisture intrusion while allowing trapped moisture to escape. These systems might be able to function like a shield against some of the impacts of climate change, safeguarding the masonry from degradation to an extent. As the long term impacts of climate change become increasingly palpable, holistic approaches to preservation may slowly emerge. Historic masonry buildings, in time, may be viewed through a lens that recognizes their vulnerability to the changing environment. Preservation strategies that encompass comprehensive site analysis, ongoing monitoring, and adaptive management are potentially useful. As Capitol Hill’s historic brick rowhomes weather the dual forces of time and environmental shifts, the combination of sustainable preservation practices, adaptive restoration strategies, and a respect for architectural heritage becomes more important. At the time of publishing this article (late August of 2023) the National Trust for Historic Preservation highlights the issue of climate change and the associated damage to historic American architectural treasures, right on their home page. ![]() The architectural floor plan above, courtesy of the Library of Congress, under a creative commons license, shows the wall layout of the Decatur House in Washington DC, the current home of the National Trust for Historic Preservation. In a future article we look even more closely at the future potential impacts of climate change on out historic brick and mortar buildings of Washington, DC. Climate change poses a range of threats to the physical structures of historic brick buildings in Washington DC. More intense and frequent weather events, such as heavy rainfall and extreme temperatures, can increase moisture exposure and water intrusion, weakening mortar and bricks. Freeze-thaw cycles, salt damage, mold growth, and shifts in vegetation and pests can further accelerate deterioration. Erosion, foundation instability, rising labor and material costs, as well as potential regulatory changes, compound the challenges. The new threat of climate change basically amplifies all past threats and concerns and elements of building deterioration from natural or environmental sources. To properly maintain, repair, and care for these historic buildings, a knowledge, interest and understanding of historic building principles is required. Here in Washington DC, historic masonry buildings are extremely expensive and the amount of financial loss caused by improper repointing and low quality construction is staggering. However, in addition to the direct financial value of the property, there is also a cultural loss when historic buildings are damaged. By comparison, consider neighboring poor cities, when historic buildings are damaged, it’s not just the loss of value to the property owner, there’s also a loss to all inhabitants and visitors of a city, present and future, who care about architecture, history, and culture. We encourage all of our clients, and all readers of this article and to our blog in general, to prioritize the historic built environment of Washington DC and neighborhoods such as Capitol Hill, Dupont Circle, and Georgetown and become educated on on the difference between proper historic preservation versus improper work which leads to significant damage to the historic fabric of a building. From a conservation and preservation perspective, several approaches can be taken to improve conditions related to deteriorated historic brick masonry. Primarily, lime mortar brick joints and low temperature fired soft red clay bricks should be inspected and checked on a routine maintenance schedule, either seasonally or at least annually. If brick masonry is kept in good condition, the life of embedded wood elements can be significantly extended. Hire a professional contractor which specializes, understands and appreciates historic construction elements and buildings. You can learn a lot more on our blog. Feel free to check it out. If you have questions about the historic masonry of your building in Washington DC, fill out the webform below and drop us a line. We will be in touch if we can help. <p>The post Deterioration of Masonry Foundations In The Presence of Moisture – Part II first appeared on Infinity Design Solutions.</p> Via https://www.ids-dmv.com/masonry/deterioration-of-masonry-foundations-in-the-presence-of-moisture-part-ii/ Roof Damaging Attachment – When Should It Be UsedFlexible flat roof solar photovoltaic mats are a possible alternative to traditional rigid parapet mounted or ballasted solar panels. The most common rooftop solar panels, in America, are generally installed by drilling holes through the flat roof parapets. Drilling or bolting through a low slope roof membrane or associated components such as parapets is extremely problematic. Flexible solar panels, also known as solar mats or solar membranes, offer some potential advantages:
![]() In the image above, you can see the flexible photovoltaic solar Mat lays directly against the TPO membrane without a metal frame or mounting through the parapet coping.
Smart proactive replacement, construction, upkeep and maintenance of low slope roof and mansard roof systems requires an enthusiastic interest and understanding of historical methodologies, waterproofing principles, and building science. Here in Washington DC, historic and modern residential and commercial buildings are extremely expensive and the roof and related systems provide the shield that preserves the building. We encourage all of our clients, and all readers of this article and to our blog in general, to prioritize the value of quality construction and building maintenance, and develop a relationship with our company. You can learn a lot more on our blog. Feel free to check it out. If you have questions about the roof and related systems of your building in Washington DC, fill out the webform below and drop us a line. We will be in touch if we can help. <p>The post PV Mats That Do Not Require Roof Damaging Attachment first appeared on Infinity Design Solutions.</p> Via https://www.ids-dmv.com/roofing/pv-mats-that-do-not-require-roof-damaging-attachment/ Entropy and decay are natural, part of deterioration of historic buildings but when managed proactively masonry facades can be effectively preserved![]() This image shows the significantly deteriorated rear masonry facade of urban rowhomes with a rear projecting cantilever at the the top floor. The cantilever was an element found in both of the buildings in the center of the image. The projecting cantilever has already collapsed at the building left of center. It looks poised and ready to collapse at the right side as well. If you look closely, you can see the openings, like beam pockets found at typical interior floor joist bearing points, left in the exterior brick masonry wall to allow the cantilevered floor joists to pass through. Entropy and deterioration happens in a nonlinear manner, increasing at an increasing rate. The outline of todayâs article follows below: Overview of entropy in masonry facadesTodayâs article explores the effects of decay and entropy on historic masonry facades, the factors contributing to their deterioration, and preservation strategies to safeguard these valuable historic assets. Entropy in historic masonry facades refers to the natural process of decay and degradation that occurs over time in these structures. Masonry facades, which are typically composed of brick, stone, or other types of masonry materials, are subject to various environmental and human-induced factors that contribute to their deterioration. In the image above you scan see this extreme deterioration that has happen to the rear facade of the building without care and upkeep. ![]() The picture above shows a small section of a rear masonry facade in CapitolHill, Washington, DC, in great need of masonry restoration, including proper tuckpointing and orvrepointing with a carefully historically accurate mortar. The concept of entropy in this context is derived from thermodynamics, where it signifies the tendency of a system to naturally move towards a state of disorder or randomness, in almost all types of buildings and building systems. In the case of historic masonry facades, entropy manifests as the gradual loss of structural integrity, appearance, and functionality of the buildingâs outer wall assemblies. These natural forces of entropy are happening sll around us, all the time, to buildings and materials. Buildings require trained and skilled care and upkeep to be preserved and resist the forces of nature to return back to dust. Several factors contribute to the entropy of historic masonry facades:
Weâll discuss further details about the items in the list above, but first weâll explain the layout and some elements of the anatomy of historic masonry facades. Understanding Historic Masonry FacadesThe historic brick masonry buildings in Washington DC, constructed over a century ago, exhibit a remarkable architectural composition comprising several key elements, some of which are described below. Brick MasonryThese buildings feature load-bearing brick walls, where bricks were arranged using lime-based mortar, creating a relatively durable facade. You can see near endless brick buildings in the historic neighborhoods of Washington, DC, over 100 years old, with historic brick facades. The brick has lasted well, but is still susceptible to damage from moisture, freeze-thaw cycles, and low temperature firing related failures. ![]() The picture above shows an area of plaster covered brick. The plaster has lmdelsminated to the point that the compromised brick substrate is exposed showing the deteriorated brick surface. Window SillsLocated beneath windows, window sills are most commonly built of ashlar carved stone and serve to direct water away from the facade, protecting against moisture infiltration by creating both a monolithic or continuous cap over the masonry wall below, made of smaller individual units of brick, in most cases, and also creating a projection which extends a bit beyond the facade. This projection allows water to run off tgecedge of the sill and fall beyond the face of the facade instead of running down the facade. This passive protection allows tge facade to stay much drier during through the majority of rain events. Varied Architectural DetailsHistoric masonry facades often incorporate decorative elements like âfreizesâ, âquoins,â âpilasters,â and âreliefs,â enhancing the aesthetic appeal and representing specific architectural styles. CornicesOrnamental projections along the roofline, usually made of metal or detailed brick patterns, or sometimes even made of wood in Capitol Hill and other DC historic neighborhoods, adding architectural elegance while also shielding the lower facade against repeated water pathways at non-wind-driven events of precipitation. ParapetsThese low walls extend above the roofline, functioning as a demarcation and separation between row or conjoined buildingâs individual roof systems and supporting coping to prevent water entry. They are mostly unseen from the ground, but at facades without mansards, a parapet is often seen at the top of the facade. Flashing and terminationsInstalled at junctions, flashings are a common component which divert water away from vulnerable areas, preventing water intrusion and or water pathways down the face of building facades. In historic times, flashing metals were often fairest alloys. Today, particular maintenance and upkeep is required to prevent Ferris metals from rust and corrosion. New roof systems, for example, in most cases are added to the top of the building but terminated above the front facades with a aluminum or TPO coated aluminum pre-bent metal flashing or drip edge. Brick Chimneys lined with terracotta fluesConstructed using bricks, chimneys facilitated ventilation and provide a pathway for smoke from interior spaces. In many cases the original fireplaces have been abandoned or sealed off left in a state or defunct encapsulation. In some cases fireplaces have had decorative panels added to seal off the front openings, both to limit drafts from the chimney cavity and keep rodents out. In modern times most houses have had HVAC or boiler heating systems added to the buildings to heat and cool the house. Anchors or TiesVertical connectors linking bricks to the interior structural components are consistently used in modern construction to enhance stability and distribute loads effectively. However, in historic construction of the time, these buildings were mostly built without vertical reinforcement. Tie backs or lateral deflection resistance have been added to many facades after original construction, in many cases. Basement or Crawlspace FoundationsBeneath the facade, typically a triple wythe basement or crawl space foundation supports the entire load path of the building. In many cases basements have been updated with modern finishes in recent decades but historically most were just root cellars with rat sabs added to deter some of the common elements of moisture and rodent entry from below. LintelsPositioned above windows and doors, lintels are horizontal structural elements typically made of stone or brick, providing support and preventing differential settlement (collapse and cave-in) above the window or door opening. In historic construction, in Washington, DC, often wooden lintels are hidden behind shallow segmented brick arches, often called âeyebrowsâ. ![]() The picture above shows an exposed CMU lintel at an old but not historic opening header which our company recently refinished to extend the life of the lintel where it would otherwise rot through from oxidation and rust. Cast Iron Front Stairs or Masonry StoopThe cast iron front stairs and masonry stoops are prominent architectural features found in many historic brick buildings in Washington DC. These elements serve as the main entrance to the building, enhancing its visual appeal and contributing to the overall architectural character. Cast iron front stairs are a distinctive feature commonly found in late 19th-century and early 20th buildings in the historic neighborhoods of Washington, DC. These stairways are designed with intricate and ornate patterns at the stair risers, often with a diamond relief at the treads. The cast iron material is somewhat durable yet lacks the ductility of steel. With proper care and upkeep, the stairs are somewhat durable to withstand the exterior elements over many decades. These stairs often include decorative railings and balusters, adding to the aesthetic charm of the entrance. Cast iron front stairs provide a sense of grandeur and sophistication, making a strong visual statement for the building. Masonry stoops are another prevalent entrance feature in the historic brick buildings of Washington, DC, particularly in rowhomes. Typically constructed using brick or stone, the stoop is a set of steps leading up to the main entrance of the building. Masonry stoops can vary in size and design, ranging from a few steps to more elaborate structures with midlandings and multiple flights of treads and risers. Like cast iron front stairs, masonry stoops contribute to the buildingâs architectural character and curb appeal. In addition to providing access to the entrance, the stoop often serves as a gathering space or a place to sit and socialize, particularly more in historic times when families lived together in these buildings across several generations. Decay and Entropy in Historic Masonry FacadesDecay and entropy in historic masonryâs facade happens for several different reasons or source causes, the list below describes several of those potential sources of introduction of deterioration of masonry facade building systems:
Preserving historic masonry facades requires understanding and managing entropy effectively. Conservation efforts typically involve careful assessment, restoration, and regular maintenance to slow down the decay process and ensure the continued longevity and cultural significance of these structures. Skilled contractors, like IDS employ various techniques such as proper historically accurate tuckpointing or repointing, and repairs to protect the masonry to safeguard its integrity and historical value. Factors Contributing to Decay and Entropy in Historic Brick FacadesWe will discuss the following main factors affecting and driving building decay and entropy in masonry facades:
Some of the most significant threats to historic brick masonry structures in Washington, DC are posed by air pollution, moisture infiltration, global warming, material properties, human activities, and neglect to historic brick masonry facades. Environmental Factors: Air Pollution and Acid RainAir pollution, predominantly caused by industrial emissions and vehicular exhaust, poses a severe threat to brick masonry facades. Airborne pollutants, such as sulfur dioxide (SO2) and nitrogen oxides (NOx), react with atmospheric moisture to form acidic compounds. When acid rain falls on historic brick facades, it initiates a chemical reaction with the calcium carbonate present in the bricks and mortar, leading to erosion and degradation. Over time, this process weakens the masonryâs structural integrity and aesthetic appeal. Environmental Factors: Moisture Infiltration and Freeze-Thaw CyclesMoisture infiltration is a common issue in older brick masonry buildings lacking modern waterproofing techniques. When water seeps into the brickwork, it can cause efflorescence and freeze-thaw cycles during colder months. As the water freezes and expands, it exerts pressure on the bricks and mortar, leading to cracking and spalling. With repeated freeze-thaw cycles, the masonry gradually deteriorates, risking irreversible damage. Environmental Factors: Global Warming and Its Impact on Masonry ConditionsGlobal warming intensifies the impact of environmental factors on historic brick masonry facades. Rising temperatures increase the rate of chemical reactions, accelerating the decay process. Additionally, increased frequency and intensity of extreme weather events, such as heavy rainfall and storms, worsen moisture infiltration issues. These factors collectively contribute to a faster deterioration of masonry structures, demanding more frequent maintenance and conservation efforts. Material Limitations: Susceptibility of Historic Low Temperature Fired Bricks and Soft Lime Mortar:Many historic brick masonry facades were constructed using low-temperature fired bricks and soft lime mortar. These materials are more porous and less durable compared to modern counterparts. As a result, they are highly susceptible to environmental factors like water infiltration, freeze-thaw cycles, and acid rain. The gradual breakdown of these materials over time poses significant challenges for preservation efforts. Material Limitations: Variation in Craftsmanship and Lack of OversightThe quality of craftsmanship during the construction and restoration of historic masonry varies considerably between contractors. Some restoration work may not adhere to proper pointing techniques, leading to compromised mortar joints and increased vulnerability to moisture infiltration. Furthermore, the absence of effective industry-specific oversight from the authority having jurisdiction in Washington, DC, may result in subpar restoration practices, further endangering the integrity of brick masonry facades. Material Limitations: Aging and Wear-and-Tear EffectsAs with any historical structure, aging and regular wear-and-tear impact the condition of brick masonry facades. Continuous exposure to natural elements, pollution, and human activities contributes to the gradual degradation of the facadeâs appearance and structural stability. Regular maintenance and timely repairs are essential to counteract the effects of aging and prolong the longevity of these historic structures. Human Neglect and Harm: Lack of Maintenance and RepairOne of the primary threats to the preservation of historic brick masonry facades is the lack of proper maintenance and timely repairs. Neglecting minor issues can lead to more extensive damage over time, necessitating costlier restoration efforts. A consistent maintenance plan, including routine inspections and immediate repair of defects, is crucial to mitigate potential deterioration. ![]() The picture above shows an example of where water entry from the exterior facade of a building has infiltrated into the interior ceiling of a bathroom causing damage, both to drywall and other interstitial hidden materials. Human Neglect and Harm: Inappropriate Restoration TechniquesInappropriate restoration techniques, such as the use of incompatible modern materials or aggressive cleaning methods, can harm historic masonry facades. Improper interventions may alter the facadeâs original appearance and compromise its historical integrity. Adherence to preservation guidelines and employing experienced conservation professionals is vital to safeguard these irreplaceable architectural gems. Human Neglect and Harm: Adjacent Urban Development and ConstructionThe presence of ongoing urban development and construction activities near historic brick masonry facades poses a risk of damage due to vibrations, increased air pollution, and potential water runoff issues. Proper planning and coordination between preservation authorities and construction agencies are necessary to protect these vulnerable structures during adjacent development. Preserving historic brick masonry facades is a multifaceted endeavor that requires addressing a range of challenges posed by environmental factors, material properties, and human activities. To ensure the longevity and cultural significance of these buildings, a proactive approach that includes regular maintenance, compatible restoration techniques, and collaboration between preservation authorities and stakeholders is essential. By protecting these historic structures, we can value our architectural heritage and preserve it for future generations. Preservation and Conservation StrategiesPreserving and conserving historic brick masonry needs to start with analyzing and understanding the current condition, planning and executing the preservation and or restoration of the facade. Conditions SurveyPerform a comprehensive conditions survey of the brick masonry facade to assess its current state. This survey should identify areas of deterioration, water infiltration, cracking, efflorescence, and other signs of damage. Understanding the facadeâs condition is crucial for developing an effective preservation plan, you can hire a company like IDS to help. Water Diversion ManagementProper water management is crucial for the preservation of historic brick masonry. Water is a significant contributor to deterioration, as it can cause efflorescence, freeze-thaw damage, and entropy and erosion of the mortar. Implement strategies to divert water away from the brick facade, including the following:
![]() The picture above shows the front facade of a building in DC. The masonry was covered with a siding which isnât very common or necessarily effective. We see some examples of other materials used as coverings over masonry in DC such as formstone, from time to time. In this case the downspout was extended away from the building because without a working underground drain, the water matriculated down into the basement in close proximity to the electrical panel. The pathway of the water was a trail of deterioration and destruction. Tuckpointing and RepointingOver time, the mortar joints between the bricks can deteriorate due to weathering and aging. Tuckpointing and repointing are techniques used to replace the deteriorated mortar and restore the structural integrity of the brick masonry. The process involves carefully removing the old mortar and replacing it with new mortar that matches the historic appearance. It is crucial to use compatible materials and techniques to avoid damaging the historic fabric of the facade during repointing. Maintenance and Regular InspectionsRegular maintenance and periodic inspections are essential for early detection of issues and prompt intervention. Implement a maintenance plan that includes regular inspections, cleaning, and minor repairs to address potential problems before they escalate. ![]() The picture above shows the rear facade of a building in DC, in a rear ell area of the building. A stair-step crack has formed. The diptych repeat of the image allows the comparison between a markup highlighting the area of structural failure. The building conditions should be surveyed regularly, at least annually to identify areas of damage to limit and deter exponentially expanding deterioration. Professional Preservation ExpertiseEngage with professionals experienced in historic preservation and conservation of masonry facades, like IDS. This ensures that all restoration and repair work is carried out in accordance with best practices and adheres to conservation guidelines. Preserving historic brick masonry facades is a delicate process that requires a thoughtful approach, expertise, and a commitment to maintaining the buildingâs historical value for future generations. Collective efforts the preserve historic facades are missingThe lack of collective efforts in safeguarding our architectural heritage through proper preservation and conservation measures is noteworthy. A authority having jurisdiction is also known as an AHJ period in areas of America such as Washington DC, for example, there are many AH jâs. One of the main AH jâs is DCRA. DCRA, for example has the authority to stop construction if the construction is being done incroperly. Osha, on Also has the ability to stop construction if itâs being done without proper safety precautions and weâre following the relevant safety rules mandated by osha related to construction. The historic review board also can impose requirements related to construction within certain neighborhoods of Washington DC. All of these different AH jâs, are examples of the various sets of requirements. Often theVarious types of requirements and/or rules are not coordinated by an overarching entity. Instead, itâs often the responsibility of the property owner to verify that all varied requirements are being simultaneously fulfilled. The governing bodies end where AH jâs in Washington DC seem to recognize the historical and cultural and even economic value of maintaining and preserving historic properties. Largely though there is very little Enforcement or even encouragement for contractors to follow best practices. The building code is one of the main standards governing the minimum requirements for quality and construction. The building code though includes very few provisions related to upkeep, maintenance, reconstruction, and or preservation and restoration of historic masonry, for example. Historic masonry upkeep and preservationTo properly maintain, repair, and care for these historic buildings, a knowledge, interest and understanding of historic building principles is required. Here in Washington DC, historic masonry buildings are extremely expensive and the amount of financial loss caused by improper repointing and low quality construction is staggering. However, in addition to the direct financial value of the property, there is also a cultural loss when historic buildings are damaged. By comparison, consider neighboring poor cities, when historic buildings are damaged, itâs not just the loss of value to the property owner, thereâs also a loss to all inhabitants and visitors of a city, present and future, who care about architecture, history, and culture. We encourage all of our clients, and all readers of this article and to our blog in general, to prioritize the historic built environment of Washington DC and neighborhoods such as Capitol Hill, Dupont Circle, and Georgetown and become educated on on the difference between proper historic preservation versus improper work which leads to significant damage to the historic fabric of a building. From a conservation and preservation perspective, several approaches can be taken to improve conditions related to deteriorated historic brick masonry. Primarily, lime mortar brick joints and low temperature fired soft red clay bricks should be inspected and checked on a routine maintenance schedule, either seasonally or at least annually. If brick masonry is kept in good condition, the life of embedded wood elements can be significantly extended. Hire a professional contractor which specializes, understands and appreciates historic construction elements and buildings. You can learn a lot more on our blog. Feel free to check it out. If you have questions about the historic masonry of your building in Washington DC, contact us or fill out the webform below and drop us a line. We will be in touch if we can help. <p>The post Entropy In Historic Masonry Facades And Structures first appeared on Infinity Design Solutions.</p> Via https://www.ids-dmv.com/masonry/entropy-in-historic-masonry-facades-and-structures/ How Does Residual Moisture In Masonry Walls Affect Its Quality?Today, we share the first post in a four-part series on building decay and deterioration, opening with the topic of residual moisture trapped within historic brick and masonry wall assemblies.
The outline of todayâs article follows: The topic of moisture trapped between brick masonry walls and plaster internal wall coverings is a common topic and source of questions for our clients and customers. Summary of water entry points through masonryMasonry walls are susceptible to water entry through several mechanisms, including capillary action, cracks, voids, and porous materials. Capillary action, a prominent cause of moisture infiltration, occurs when water is drawn into the fine pores and capillaries of the masonry material due to surface tension and molecular attraction. This phenomenon allows water to move upward against gravity, leading to water accumulation within the masonry wall. Double wythe masonry exterior walls with a plaster finish can be over 9-inches thick. Although historic masonry elements generally have higher perocity then modern or contemporary Portland type machinery or motor, the historic motor will often dry very slowly. It can be a bit counterintuitive, naturally people think of higher curiosity surfaces or substances having the ability to dry faster, however lime mortar can dry out extremely slowly. Compared to Portland type mortars, lime mortars have an open structure, which increases the porosity but also increases the amount by which water is entrenched and embedded deep into the structure of the mortar. This issue comes up frequently when talking about brick pointing, tuckpointing and repointing. Unlike Portland cement, which forms interlocking crystalline structures during curing, lime mortar remains in an amorphous state. This lack of crystalline formation contributes to the slower drying time. Lime mortar has a more open-pore structure compared to modern cement-based mortars. This allows for better vapor transmission and moisture movement, making it more breathable. As a result, moisture within the lime mortar takes longer to evaporate or migrate out of the material. The image above shows the long term effect of moisture trapped in a plaster and brick wall assembly, emphasizing the need for preservation and conservation to protect the historic masonry from further decay. You may notice the cellulose paper face of a wallboard in the discombobulated hodgepodge of materials. The picture above shows so much at once because you can see the exposed face of the substrate brick covered in efflorescence with gaping and deteriorated lime mortar joints, the interstitial materials, and the undemolished wall all in one view. If you look closer, in the photo below, layers of gypsum at the surface with yellow-brown. We are more focused on the issues of hydrated plaster and water trapped between solid double (or triple, in some cases) wythe masonry walls and plaster which is applied directly to the face of the brick masonry wall. In this case, that sandwich of materials is present in this example, but thereâs an extra element which is common in all types of historic buildings in Washington, DC: drywall or wallboard or plasterboard was applied on top of the plaster in layer decades after the original construction.
When drywall is exposed to moisture or water, the following sequence of events takes place: 1. Water AbsorptionThe paper facing is porous, allowing it to absorb water readily. When the drywall comes into contact with moisture, the paper absorbs the water like a sponge. 2. Hydrolysis and Lignin DegradationAs water is absorbed into the paper, hydrolysis occurs, breaking down the bonds between the molecules in the lignin present in the paper fibers. 3. Oxidation and YellowingThe oxygen dissolved in the water reacts with the broken-down lignin molecules, causing them to undergo oxidation. This oxidation process leads to the formation of chromophores, which are responsible for the yellowish coloration. 4. Further Degradation and BrowningWith continued exposure to moisture or water, the lignin degradation and oxidation continue, leading to further darkening of the paper, eventually turning it brown.
When the cellulose paper face of drywall becomes wet, mold spores that are naturally present, abundant even, in the air can settle on the moist surface and start to grow. Once the mold spores find a suitable environment with organic material and moisture, they rapidly multiply and form visible patches of mold on the paper facing. The historic Washington, DC neighborhoods are filled with structural brick framed buildings. However, these buildings are generally over 100 years old and in need of particular care and upkeep, by specialists who understand historic masonry preservation. Deterioration invariably leads to deterioration and the detrimental effects of water infiltration. Moisture can seep into old masonry walls through various entry points, leading to structural damage and decay over time. In this article, we will delve into the challenges posed by moisture in masonry, the traditional historic masonry wall assembly composition, and the factors affecting the rate of moisture movement. We will also explore techniques for preventing structural damage and decay, along with monitoring and assessment methods for historic masonry upkeep and preservation. Capillary action in masonry wallsCapillary action can draw moisture through masonry walls. Capillary action allows, or causes, water to migrate through seemingly solid materials. Capillary action is the movement of liquids through narrow spaces, like thin tubes or porous materials, due to cohesive and adhesive forces. Molecules at the liquidâs edges stick to surfaces (adhesion), while intermolecular forces within the liquid pull it upward (cohesion), defying gravity in capillaries. ![]() ![]() The water entry, and related damage caused by capillary action in historic lime mortar brick masonry arises from the same process that enhances its durability. When moisture infiltrates the deteriorated, and tgerefore overly porous, mortar joints, in need of repointing or tuckpointing, capillary action draws moisture into the lime mortar joints, initiating a cycle of absorption and evaporation. Over time, this incessant moisture movement leads to further erosion and decay within the mortar, weakening the entire masonry structure, in a vicious cycle, at an increasing rate. Additionally, freeze-thaw cycles in colder climates exacerbate the problem. The repeated expansion and contraction due to freezing and thawing further deteriorate the mortar, causing cracks and disintegration. As a consequence, the structural integrity and weather-defensive shell of historic buildings can be compromised, necessitating preservation efforts, more extensive than just repointing with compatible lime mortar and addressing sources of water ingress. In this example, extreme damage to the interior plaster resulted from unmitigated exterior masonry joint deterioration. This problem could have easily been stopped, right in its tracks by proactive brick tuckpointing. As a related consideration, but a side note, the issue of capillary action is also a factor, or force, in hydrostatic pressure in underground water movement, including at basement and foundation ground water leakage. When the surrounding soil or ground is saturated with water, it exerts pressure on the lower portion of the wall, facilitating capillary rise. This phenomenon can result in dampness and damage to the interior surfaces of the structure, compromising its stability and aesthetics. Traditional historic masonry wall assembly compositionHistoric masonry walls were constructed using lime mortar, which has been widely favored for its ability to accommodate slight movements without cracking. The wall assembly typically consists of bricks or stones joined together with lime mortar. Lime mortar allows some breathability, permitting moisture to escape, thereby reducing the risk of trapping water within the wall. Challenges with moisture in lime mortarWhile lime mortar offers certain advantages (re-calcification, bond, workability, lower embodied energy), it is not impervious to moisture-related challenges. Over time, lime mortar will deteriorate, leading to gaps and cracks that allow water infiltration. Additionally, soluble salts present in the mortar and masonry can exacerbate moisture-related issues. The build-up of these salts can cause efflorescence, a white crystalline deposit, further deteriorating the masonryâs surface. The pictures below show an early CMU foundation in Northeast Washington DC. The foundation was built at an interesting time, just before the advent of modern liquid applied foundation waterproofing polymers, but after the beginning of the use of Portland and lime combined mortars. ![]() ![]() Similar to the problems experienced in the wall shown above with residual exposure to excess moisture, historic lime binder brick mortar faces similar challenges. Plaster directly attached to brick surfaces
The adjacent picture shows an interior plaster brown-coat wall covering. This plaster is applied directly to the historic common brick wall substrate. When moisture enters through the open or permeable mortar joints of a brick wall, in this case: a double whythe brick composition, the moisture is then trapped within an assembly of plaster and brick. The moisture will continue to permeate and move across the assembly, but it moves slowly. Factors affecting the rate of moisture movementSeveral factors influence the rate of moisture movement in masonry walls. These factors include climate conditions, such as rainfall and humidity levels, as well as the type and porosity of the masonry materials used. Additionally, the presence of cracks, gaps, and capillaries within the masonry greatly impacts the rate of moisture infiltration. Entropy and building decay
Monitoring and assessment techniques
Historic masonry upkeep and preservationPreserving historic masonry requires a delicate balance between conserving the original materials and incorporating effective modern conservation practices. Repointing with compatible lime mortar, plaster repair using breathable materials, and controlled dehumidification are some of the strategies employed for the upkeep and preservation of historic masonry walls. A well-executed preservation plan ensures that the architectural integrity and historical value of the structure are retained for future generations to appreciate. ![]() ![]() To properly maintain, repair, and care for these historic buildings, a knowledge, interest and understanding of historic building principles is required. Here in Washington DC, historic masonry buildings are extremely expensive and the amount of financial loss caused by improper repointing and low quality construction is staggering. However, in addition to the direct financial value of the property, there is also a cultural loss when historic buildings are damaged. By comparison, consider neighboring poor cities, when historic buildings are damaged, itâs not just the loss of value to the property owner, thereâs also a loss to all inhabitants and visitors of a city, present and future, who care about architecture, history, and culture. ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() We encourage all of our clients, and all readers of this article and to our blog in general, to prioritize the historic built environment of Washington DC and neighborhoods such as Capitol Hill, Dupont Circle, and Georgetown and become educated on on the difference between proper historic preservation versus improper work which leads to significant damage to the historic fabric of a building. From a conservation and preservation perspective, several approaches can be taken to improve conditions related to deteriorated historic brick masonry. Primarily, lime mortar brick joints and low temperature fired soft red clay bricks should be inspected and checked on a routine maintenance schedule, either seasonally or at least annually. If brick masonry is kept in good condition, the life of embedded wood elements can be significantly extended. Hire a professional contractor which specializes, understands and appreciates historic construction elements and buildings. You can learn a lot more on our blog. Feel free to check it out. If you have questions about the historic masonry of your building in Washington DC, contact us or fill out the webform below and drop us a line. We will be in touch if we can help. <p>The post Trapped Residual Moisture In Masonry Walls â Part I first appeared on Infinity Design Solutions.</p> Via https://www.ids-dmv.com/masonry/trapped-residual-moisture-in-masonry-walls-part-i/ A picture below shows a historic brick building wall corner with damage where the wall was touched by a passing truck. The wall has also been repointed terribly by a contractor who was wholly unskilled in the practice of masonry restoration. Today’s article is a case study examining the attempts and failures in preservation and restoration leading to a poorly treated masonry building and follows the outline below:
Historic brick masonry structures should be treated like something special and unique, more than another tract home in the sea of urban sprawl just outside of our historic city center. The historic brick masonry buildings of DC are unique. They are essentially artifacts from history, limited in quantity with reducing numbers sl ost every day. They shoukd be treated as something of value. Preserving these historic brick buildings requires an understanding of history and engineering and professional restoration practices. In this today’s discussion, we will delve deeper into the science behind the dangers of using hard mortar in historic brick masonry. We will examine the principles of proper tuckpointing and explore damage mitigation strategies like bollards. Additionally, we will look at the cost-effectiveness and efficacy of skillful repointing and the challenges of removing sloppily applied mortar from fragile historic bricks. Lastly, we will discuss the architectural significance of brick infill and the distinctions between historic pressed and common bricks. The next picture below shows a closer view of the picture above at the point of damage where three bricks have been broken by a closely passing truck that merely touched the face of the bricks at the outside corner and calls those bricks to crack and break. The Use of Bollards to Protect Brick Facades in Tight AlleywaysHistoric brick facades, especially at corners and in narrow alleyways, are susceptible to damage caused by vehicular impact. The forces exerted by vehicles during collision events can lead to catastrophic structural failure and compromise the safety of pedestrians and occupants, we have seen a few extreme examples right here in Capitol Hill. Bollards are an option, in some cases, designed to mitigate this risk by providing a physical barrier against vehicle impact. Bollards, when properly installed, function as force-absorbing barriers that dissipate impact forces and prevent direct contact with the brick facade. They distribute the forces over a larger area, even into the cantilevered concrete footing reducing localized stresses on the brickwork. By selecting appropriate bollard materials, such as steel tubing in combination with reinforced concrete, bollards are durable and often effective in protecting the historic brick masonry. The Dangers of Using Hard Mortar in Historic Brick MasonryIn the in addition to the damage caused by impact from a vehicle, the wall has also been very sloppy repointed using the wrong type of mortar. it’s extremely important to use a proper historic lime mortar when repointing historic brick and masonry facades. Some untrained contractor used a Portland cement mortar, at the wall shown here, the type bought off-the-shelf at a big box store. Big box stores unfortunately don’t sell the type of mortar required to repoint and restore historic masonry. Even right here in Washington DC, we have two large big box stores selling the type of mortar that can’t be used on the historic buildings of Washington DC, Realtors and property managers throughout the city, trying to make a quick buck, will often send their unskilled laborers out to purchase this incorrect type of cement and use the resulting mortar incorrectly to point up brick facade walls like the one shown in the photos below. Historic brick masonry was designed to withstand the forces of time and the environment. Traditional bricks were softer and more porous than modern bricks. Using hard cement-based mortars with these delicate bricks creates a mismatch in material properties. Hard mortars lack the flexibility required to accommodate the natural expansion and contraction of historic bricks due to temperature variations. This inflexibility leads to differential movement between the bricks and the mortar, resulting in internal stress, cracking, and spalling. Modern Portland cement-based mortars are rigid and non-porous, which inhibits the bricks’ ability to “breathe” and release moisture. This trapped moisture can freeze and expand during colder temperatures, causing micro-cracks and further weakening the brickwork. In contrast, historic lime-based mortars are more compatible with the softer bricks, providing the necessary breathability, flexibility, and self-healing properties. The next picture below shows the damage brick from an even closer angle. From this perspective you can see the original motor at the area where the bricks were broken. The new motor has been smeared on top of the face of the bricks and on top of even the damaged area of mortar, overlaying the top of the brick joint. After having worked with brick and mortar for decades, it’s hard to imagine how someone can even do this type of work where it looks so bad. Even when training new machinery apprentit’s in the beginning, right when they start, they can generally do a much better job than this. Why Proper Tuckpointing is ImportantTuckpointing is an essential restoration process that involves replacing deteriorated mortar joints with compatible materials. Decades of time can elapse between repointing iterations if the work is done properly. The primary objective is to maintain the structural integrity, restoring moisture resistance properties, and simultaneously enhancing its visual appeal. Proper tuckpointing minimizes water infiltration, which can accelerate the decay of historic bricks and weaken the building’s overall stability. Historic masonry structures are subjected to various environmental stresses, including moisture, temperature fluctuations, and air pollutants transferred to buildings by acidic rain. When the mortar joints start to deteriorate, water can seep into the brickwork, compromising its strength and promoting the growth of destructive microorganisms, often referred to in the preservation discipline as biocolonization,like algae and fungi. The appropriate choice of mortar type, such as lime-based mortars, ensures compatibility with the historic bricks, facilitating better adhesion and allowing for the desired flexibility. It’s cheaper to do it right the first timeRepointing is a restoration process where damaged or deteriorated mortar joints are replaced. It is essential to use skilled contractors, like IDS, who understands the principles of historic masonry restoration to ensure that the new mortar is historically compatible with the specific historic bricks of each particular facade of a building. A successful repointing process improves the overall structural stability, resistance to the elements, and longevity of the building. The success of repointing lies in the careful selection of compatible proper substrate and subcomponent materials and the proper application of repointing processes. An understanding of the properties of both the historic bricks and the mortar is crucial. Lime-based mortars, with their lower compressive strength and higher permeability, allow the historic bricks to maintain their breathability and accommodate moisture movement, reducing the risk of frictional damage. The picture below shows a close up view of the improper motor used in the repointing of a historic building. The motor is smeared all over the face of the historic brick in a slapdash sort of mess. A once beautiful historic building now looks just like a type of thrown up collection of salvaged garbage. In this sloppy state it couldn’t even accidentally be mistaken for a German smear effect. Challenges of Removing Sloppily Applied Mortar from Historic BrickSloppily applied mortar is a common issue in the restoration of historic brick masonry. Aggressive removal methods, such as sandblasting or mechanical grinders, can cause significant damage to the fragile historic bricks. Preserving the unique texture and character of historic bricks requires a scientific approach to identify suitable removal techniques. Historic bricks are more porous and softer than modern bricks. The abrasive force of sandblasting or mechanical grinders will invariably erode the brick’s facing surface, resulting in further damage and increased susceptibility to moisture absorption. A thorough examination of the historic bricks’ physical properties and a thorough understanding of the compatibility of mortar removal methods are necessary before even attempting cleaning. This type of damage is significant, yet can happen so quickly from using an untrained contractor. In some cases, using non-abrasive removal techniques, such as chemical poultices and low-pressure water wash, the restoration can partially remove the slapdash mess of mortar, but the efficacy of this type of tedious process is limited and extremely costly. Brick Infill When Doors or Windows are Removed from Building FacadesAs historic buildings undergo adaptive reuse, there may be a need to remove doors or windows. Brick infill is a restoration practice employed to maintain the building’s visual cohesiveness and structural stability. Engineering principles are crucial in selecting the appropriate bricks, mortar, and infill design to ensure a seamless integration with the existing brickwork. Removing doors or windows leaves gaps in the brick facade, which, if not properly addressed, can compromise the building’s integrity and thermal performance. Carefully matched bricks and compatible lime-based mortars are essential to create a uniform appearance and maintain structural integrity. Historic Pressed Bricks vs. Historic Common BricksHistoric brick masonry encompasses various brick types, each with its own unique characteristics and properties. Understanding the distinctions between historic pressed bricks and historic common bricks is essential for proper restoration and repair practices. Historic pressed bricks are manufactured by pressing clay into molds, resulting in a uniform and smoother surface finish. The uniformity of pressed bricks makes them ideal for facing and providing a more refined and elegant appearance to the building’s exterior. On the other hand, historic common bricks are made by hand, leading to a more irregular texture. These bricks are typically used in the building’s core, where their rougher texture may not be visible but still contributes to the overall structural strength. Understanding the differences between historic pressed bricks and historic common bricks empowers restoration professionals to make informed choices when sourcing materials and ensuring the authentic preservation of these remarkable architectural treasures for future generations to appreciate and cherish. Through the thoughtful application of architectural engineering and scientific restoration practices, we can safeguard these historic gems and continue to celebrate their cultural and historical importance for many years to come. Preserving historic brick masonry requires a scientific approach that draws on professional restoration principles and practices. Understanding the risks associated with hard mortar, the significance of proper tuckpointing, and the importance of protective measures like bollards is crucial in maintaining these valuable cultural heritage structures. By embracing the scientific reasoning behind material compatibility and the importance of skilled craftsmanship, contractors like IDS can successfully repoint historic brick masonry structures, ensuring their longevity and visual appeal. Moreover, the insidious damage caused by sloppily applied mortar can be so extreme that it can exponentially damage a building. Historic masonry upkeep and preservationTo properly maintain, repair, and care for these historic buildings, a knowledge, interest and understanding of historic building principles is required. Here in Washington DC, historic masonry buildings are extremely expensive and the amount of financial loss caused by improper repointing and low quality construction is staggering. However, in addition to the direct financial value of the property, there is also a cultural loss when historic buildings are damaged. By comparison, consider neighboring poor cities, when historic buildings are damaged, it’s not just the loss of value to the property owner, there’s also a loss to all inhabitants and visitors of a city, present and future, who care about architecture, history, and culture. We encourage all of our clients, and all readers of this article and to our blog in general, to prioritize the historic built environment of Washington DC and neighborhoods such as Capitol Hill, Dupont Circle, and Georgetown and become educated on on the difference between proper historic preservation versus improper work which leads to significant damage to the historic fabric of a building. From a conservation and preservation perspective, several approaches can be taken to improve conditions related to deteriorated historic brick masonry. Primarily, lime mortar brick joints and low temperature fired soft red clay bricks should be inspected and checked on a routine maintenance schedule, either seasonally or at least annually. If brick masonry is kept in good condition, the life of embedded wood elements can be significantly extended. Hire a professional contractor which specializes, understands and appreciates historic construction elements and buildings. You can learn a lot more on our blog. Feel free to check it out. If you have questions about the historic masonry of your building in Washington DC, contact us or fill out the webform below and drop us a line. We will be in touch if we can help. <p>The post Brick Pointing And Pressed Bricks Case Study first appeared on Infinity Design Solutions.</p> Via https://www.ids-dmv.com/masonry/brick-pointing-and-pressed-bricks-case-study/ |
About UsInfinity Design Solutions LLC (IDS) is a full service general contracting company in the heart of the Dupont Circle neighborhood of Washington, DC. We focus on repair and renovation of buildings and facilities in both historic designated neighborhoods and the commercial-zoned central business district of the city. Follow Us
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