Segmented window headersIn historical brick architecture, archways support the superimposed load of the structural wall above an opening for a window or doorway. For example, historic brick masonry, the individual bricks are smaller than the window opening or door opening and if there isn’t a structural head. Or to span that opening. Then the individual bricks will, over time, fall into the opening itself and allow the portion of the wall above to collapse. The fundamental principle behind arches is their ability to distribute and transfer the weight of the structure above them, allowing for larger openings without compromising structural integrity. Archways are designed to transfer the downward force (load) from the structure above them to the supporting pillars or walls on either side. This transfer and support of the load is achieved through the compression and outward thrust of the arch. A keystone or radius at the top of the arch locks the stones or bricks in place, creating a stable and self-supporting structure. A self-supporting Roman header, in the form of a semicircular arch, is a perfect example of inherent strength and stability of a true arch. In this design, the arch distributes the load along its curve and down the supports, eliminating the need for additional reinforcements. The Pantheon in Rome is a classic example of the successful implementation of large, self-supporting Roman arches. In contrast, a segmented arch is partially self-supporting but not fully. It typically features a curved shape but relies on additional internal support. This support often comes in the form of a hidden wooden timber or steel beam within the arch. The segmented arch allows for a more flexible design, especially when accommodating different architectural styles and structural considerations. The segmented brick arch is extremely common in many parts of Washington DC, particularly in Capitol Hill. Capitol Hill was neighborhood built over a 100 years ago and at the time of its original construction many of the houses were built just for working class people. At the time the segmented arch was a way to give a building a bit more fenestration for a lower cost than stained or honed curved or radius glass. Roman arches, for example required a stained glass or radius glass to fill the top and still use the entire sub-header section as fenestration. That stained glass or radius glass was expensive then, like today. To make it all cheaper, the segmented arch allowed for a rectilinear window without either the extra expense of radius glass or stained glass and without am=n overall shorter respective area of fenestration. Historic window openings often include areas or details of craftsmanship and attention to detail not found in contemporary or modern production style construction. Including the Mc-Mansion tract homes across our MD-DC-VA suburbs. Surrounding an archway, you might find decorative elements such as moldings, voussoirs (wedge-shaped stones or bricks forming the arch), and keystones. In many cases in historic areas, like Capitol Hill, these buildings are often over 100 years old. These elements not only serve structural purposes but also contribute to the aesthetic appeal of the architecture. In the picture below, a double rowlock course of brickwork is used to create the eyebrow window header. This is a more simple, utilitarian type of historic masonry. It has no embellishments or adornments but is very common in what may have been one of the thousands units of worker’s housing over a hundred years ago. Today, in 2024, these once simple and functional houses are valued at near $1,000 / SF, making them some of the most expensive houses in America and the world. A typical window opening consists of a sill at the bottom, supporting the window frame or sash. On either side, there are jambs that support the vertical load. The lintel or header spans the top of the opening, providing horizontal support. In the case of arched windows, this header takes the form of an arch. Understanding the differences between self-supporting Roman arches and partially self-supporting segmented arches provides insight into the versatility of architectural design. While both contribute to the structural stability of window openings, the choice between them often depends on the aesthetic preferences, architectural style, and structural requirements of a particular building. More than anything else, the actual driving force behind the prevalence of segmental arches in Capitol Hill was the ceiling height to fenestration ratio. Hence, simple economics drove the use of segmented arches more than anything else. Soldier Brick CourseSoldier courses in brickwork serve both functional and aesthetic purposes in historic building facades, contributing to the structural integrity and visual appeal of the architecture. These distinctive brick arrangements are characterized by bricks standing on end with their narrow sides facing outward, creating a vertical and regimented pattern. The use of soldier courses has been prevalent throughout history and remains a prominent feature in many historic buildings at accent locations. One of the primary functions of soldier courses can be to provide structural support to the masonry wall of the facade element at a point bearing location. By placing bricks in an upright position, the load-bearing capacity of a spot in a wall may be enhanced. This is particularly significant in areas where additional strength and reinforcement are required in a point bearing position Soldier courses help distribute the load of the masonry above them more evenly. This is achieved by creating a vertical arrangement that disperses the weight downward. The rigid and upright nature of soldier courses assists in preventing the deformation or sagging of the brickwork over time, but if and only if the substrate under the point load of the soldier course is particularly strong and stable. In fact, the use of soldier courses for structural purposes may be useful in some structural conditions; it is quite rare, for structural purposes in historic areas built around the turn of the 19th-20th century, such as Washington DC. Soldier courses add a distinctive architectural detail to the facade, breaking up the monotony of horizontal brick courses. This detailing reflects the craftsmanship of the builders and contributes to the overall character and identity of the structure. When selectively placed, soldier courses can draw attention to specific architectural features. For example, they are commonly used as a band coincident with or near floor levels between levels of windows to provide a break in the monotony of a field bond, creating a visual differentiation in the facade. The vertical orientation contrasts with the horizontal lines of standard brickwork, creating a visual effect. Many historic buildings feature soldier courses as a characteristic element of their architectural style. The use of soldier courses in brickwork became particularly popular during certain historical periods, such as the Victorian era. Preserving and or restoring these elements in historic preservation buildings helps maintain the authenticity and aesthetic continuity of the structure. The common alternatives such as formstone, stucco, and parging are a travesty because they rob the building of its historic unique elements for the rest of time. The use of soldier courses often aligns with specific architectural styles and historical periods. For example, the soldier course may be a key feature in Georgian or Colonial Revival architecture. Its inclusion reflects the design preferences of a particular era and contributes to the historical narrative of the building. In the picture below you can see an example of a soldier course at the top of a wall of a historic carriage house. This wall is a relatively simple on adorned continuous bond of common brick. but this specific soldier course as one unique element of flare and architectural interest to an otherwise monotonous wall. Mansard RoofThe mansard roof is named after the French architect François Mansart who worked through the middle of the 18th century, although it was popularized by his great-nephew, Jules Hardouin-Mansart in the late 17th and early 18th centuries. Jules Hardouin-Mansart extensively used mansard roofs in the architectural designs of the Palace of Versailles during the 17th century. The mansard roof is characterized by its steeply sloping sides with a flat or gently sloping top, often punctuated by dormer windows. The tax evasion, though, may have been the actual driving force of the origin of the mansard roof. During the 18th century in France, there was a tax based on the number of stories of a building. By designing structures with mansard roofs, architects could create an additional story hidden away in what appeared to just be an attic roof space. The upper part of the mansard roof, which appeared hidden in the roof, was often used as living space. This architectural strategy allowed property owners to evade taxes by exploiting the particular regimented construct of tax regulations of the time. In Washington, DC, mansard roofs are prevalent, particularly in neighborhoods like Capitol Hill. However, the use of mansard roofs in D.C. is not typically associated with tax evasion but rather with architectural style popularized many decades earlier. Here in the USA, mansard roofs became popular during the Second Empire architectural style, which was prevalent in the mid to late 19th century. This style, characterized by elaborate detailing and the use of mansard roofs, gained popularity in the aftermath of the Civil War. Many neighborhoods in Washington, D.C., have requirements to preserve historic architecture, and mansard roofs contribute to the charm and character of these areas. The use of mansard roofs reflects the influence of architectural styles that were in vogue during the city’s expansion in the late 19th century. Mansard roofs are commonly found on rowhouses in D.C., especially in neighborhoods with Victorian and Second Empire-style architecture. They are also present on some larger institutional buildings, adding a distinctive visual element to the cityscape. While the historical origin of the mansard roof involves tax considerations in France, the use of this architectural feature in Washington, D.C., is more closely tied to stylistic preferences and historic preservation efforts rather than tax evasion strategies. Today, it’s an interesting example of how architectural elements can transcend their original purposes and become integral to the identity of a city’s built environment. The picture above shows an example of a somewhat typical mansard roof on the top of the front facade of a city rowhome. This particular mansard rooftop happens to be clad with a historic terracotta tile. Although this type of tile covering is somewhat common in the historic neighborhoods of Washington DC, it’s not nearly as common as slate roofing on mansard roofs. Historic Water TableWater tables in historic row home facades, such as those in Capitol Hill, Dupont Circle, and Georgetown neighborhoods in Washington, D.C., serve both functional and aesthetic purposes. A water table is a projecting ledge or molding built into the lower part of a masonry facade, typically at the base of a building, just above ground level. There are also several functional purposes of water tables.Water Management: The primary purpose of a water table is to manage water runoff from rain and prevent it from saturating the lower portion of the masonry facade. By extending outward, the water table helps direct rainwater away from the building, protecting the foundational masonry from excessive moisture. Preservation of Masonry: Water tables play a crucial role in preserving the integrity of the masonry. By preventing excessive moisture contact with the lower portion of the facade, they minimize the risk of water infiltration, which can lead to long-term deterioration of the brickwork and mortar. Hydration, or the absorption of water by masonry, is a significant factor in the degradation of historic buildings. Water tables help prevent staining on the facade caused by water runoff. By guiding water away from the building, they reduce the likelihood of mineral deposits, efflorescence, or other stains that can mar the appearance of the masonry. Where water drips run down a building facade, they tend to run in concentrated drip trails and these concentrated areas leave stains of both dirt and biocolonization. Biocolonization is a term used to describe plan and fungus growth of masonry surfaces. These biological life forms start small but over time can deteriorate masonry surfaces in an insidious way. Future deterioration continuously but even more rapidly as it goes. When well integrated into a facade, the water table, unlike the ugly functional tubes used in contemporary architecture of gutter and downspouts, looks like a classic architectural adornment. Water tables are often designed to seamlessly integrate with the architectural style of the building. They can be decorative elements, featuring molding or detailing that complements the overall design aesthetic. Unlike modern gutters, which are typically added to the exterior, water tables are built-in, forming an integral component of the masonry structure. This not only enhances their functionality but also contributes to the historic character of the building. Water tables contribute to the visual appeal of historic row homes. They provide a distinct horizontal line that breaks up the verticality of the facade, adding architectural interest and defining the base of the building. Water tables in historic row home facades in Washington, D.C., and other parts of the city play a role in managing water runoff, preserving masonry, and preventing deterioration. The picture above shows a historic water table and adorning cornice, but the next picture below shows a different style using pressed tin which has a artistic shape set into the sheet metal. 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, fill out the webform below and drop us a line. We will be in touch if we can help. In this coming week’s article, we’ll take a look at decorative cornices, corbels, gothic brick chimney arches for flue rain caps, jack arches and historic wrought iron elements used in the original construction of these historic brick buildings, and more. <p>The post Architectural Details in Masonry Facades – Part III first appeared on Infinity Design Solutions.</p> Via https://www.ids-dmv.com/masonry/architectural-details-in-masonry-facades-part-iii/
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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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