Here in Virginia, much of the written history connected to many old properties has been lost. Many records were burned during the Civil War and so documentation relating to many historic structures has been lost. This means that the date of construction for many old buildings remains uncertain. There are various ways that historic archaeologists have learned to get an idea of the date of historic buildings. Perhaps the most conclusive and scientific way to date a historic building is through dendrochronology, tree-ring dating. Though this method can be extremely precise in dating wooden structures, there are times when there is not enough old wood remaining suitable for a conclusive result. This method is also relatively expensive, especially when dealing with multiple structures like the various out outbuildings on a farm. Evaluating the style of architecture and the building materials used are another important way to get some idea of the age of a structure. The differences in brickwork through history are marked and easily distinguished. To understand the different brick bonds it is important to understand the difference between headers and stretchers. Headers are bricks which are laid perpendicular to the face of a brick wall. Stretchers are bricks which are laid parallel to the face of a wall. By using a combination of headers and stretchers a wall not only gains strength but also the possibility of decorative patterns arises. Each row of bricks laid one upon another in a wall is referred to as a course. Flemish bondFlemish bond along with English bond is one of the two common brick bonds used in Colonial Virginia before about 1790. Its use in Virginia began with the earliest settlers and was popular in brick structures from the 17th century until the late 18th century. Flemish bond consists of courses of alternating headers and stretchers. The headers in one course are aligned with the center of the stretchers in the next course above and below. Each alternating course begins with a header at the corner. For corners of buildings, closers (bricks cut to a smaller width) are laid in alternate courses next to the quoin header (a brick at a corner which acts as a header on one side of a structure and a stretcher on another). Flemish bond was often favored for its decorative appearance. In especially grand Flemish bond structures headers were glazed for contrast. This brick bond was commonly used on grand structures and Government buildings. Its use persisted on formal buildings in traditional Hanover County, Virginia until the 20th century. English BondThe other common brick bond in Colonial Virginia was English bond. English bond and Flemish bond were favored throughout Colonial, with few exceptions. English bond was used in structures dating from the 17th century until the late 18th century when it was replaced by common bond. Enlgish bond consists of alternating courses of headers and stretchers. While less ornamental than Flemish bond, English bond was very strong. It is often favored in foundations were its appearance is less noticeable and and its strength is useful. It was a common practice for foundations to be laid in English bond and for the facade above the water table to be laid in Flemish bond. common bondCommon bond, also called American bond, like English bond consists of alternating courses of headers and stretchers. Unlike English bond in which a header course occurs in each successive course, common bond has several adjacent courses of stretchers between each row of headers. This bond is further distinguished by the number of stretcher courses in between header courses. For example, if there are five courses of stretchers in between header courses, this would be referred to as 5-course Common bond. First occurring as three-course common bond as early as 1790 in Virginia, common bond became the standard throughout the 19th century and its use continues today. By 1800 or 1810, common bond had virtually replaced English bond. In its earliest form, bricks were laid in 3-course common bond. From about 1790 until about 1825, 3-course American bond was the standard. Then around 1825, the header courses began to move even further apart as 5-course American bond became the standard. Around the 1850's, header courses move 6 and then finally 7 courses apart. The standard form of common bond today has 7 courses of stretchers between each header course. In many cases, this bond may have some variation, and may range between 5 and 7 courses of stretchers between header courses, for example. In this case it would be apt to consider the course of the greatest number of stretcher courses as the dominant bond for dating. running bondRunning bond is a brick bond consisting of only stretchers. Bricks within every course are aligned with the center of the bricks of the adjacent courses. This bond is not conducive to building thicker brick walls more than one course deep, because there are no header bricks connecting multiple courses. Running bond was often used for veneers and for small structures which do not have space for multiple widths of brick like the narrow tops chimneys. This bond is not traditionally used for structural walls but has been used in non-structural applications for centuries as well as for structures where a great deal of strength is not required. For small structures and small additions to buildings which do not support much weight, like pents, running bond was often used. Running bond may be somewhat inconclusive for dating in many applications, but it was very uncommon generally to see it used for buildings, walls, foundations, or facades until the 20th century. types of brick and mortar as an additional cluesIn the 17th, 18th, and 19th centuries, most bricks were made by hand from clay and fired in brick clamps. These bricks had a courser texture than modern bricks and they were softer. They were mortared with soft lime mortar, traditionally made from oyster shells. Though Portland cement was invented around 1824, it was not until around the turn of the 20th century that Portland cement and smoother, modern bricks began to replace the more traditional brick and mortar. Though it may take some practice, a trained eye can recognize the differences between hand fired bricks and modern bricks; and lime mortar and modern cement. These details can provide additional clues for dating a building by the brickwork. Modern cement is much harder than lime mortar, and much harder than old bricks as well. When historic bricks are mortared with modern Portland cement, moisture is forced through the bricks themselves (the path of least resistance) which can result in various sorts of damage to the brickwork. Though Portland cement is known to damage soft, old brick, many old buildings have been patched and repointed with cement by contractors ignorant of the results. It is important to investigate thoroughly. We have an old mysterious foundation here, which seems to be mortared entirely with modern cement. But upon closer investigation, this is all a modern re-pointing, and inside the structure, the original lime mortar is visible. notes on dating buildings using brick bondsIt is important to note that, dating a building by its brick bond is not a conclusive or definitive method. But a great deal of insight may be deduced from a building's brick bond, which can help to corroborate the dates suggested by tax records, architectural styles, building plans, saw marks on wood, or nail type etc. One difficulty with using brick bonds for dating historic buildings is that each different bond was used for a relatively long time. While it may be possible to deduce with a fair amount of certainty that a building constructed in English bond was built before 1800, it would be difficult from this clue alone to know whether the building was constructed in 1790 or 1650. Another potential problem with this system is that many buildings have been repaired or added onto over time. It is entirely possible that a crumbling foundation was repaired, rebuilt, or covered at some point in the life of a building using the current methods. Additions also may conceal or obscure older brickwork, so it is always a good idea to study a building thoroughly, inside and out, looking for evidence of repairs or additions before making any conclusions. Along with other evidence, brickwork can be a useful tool for establishing the general dates of a building and its additions. For example, we have a general idea of the history of Quietude, in Hanover, Virginia which is corroborated by the brickwork. The 1 and 1/2 half story cottage was built in the early 19th century with a side passage plan. The brick work in the oldest portion of the house is 3-course common bond. We have read that the house was expanded around 1876, adding rooms to create a central passage plan. The brick work in this portion of the house is 5-7 course common bond. Around 1900, several pents were added for closet space and to provide ingress and egress from the English basement. The brickwork here is laid in running bond. In this case, the brick work and other evidence corroborates the written accounts we have found giving approximate dates for the structure. Further evidence for the accuracy of these dates is provided by the style of moldings, the plan of the house, the type of lath, saw marks on wood, and the types of nails used in construction. But the written accounts we have are all modern, and the evidence remains somewhat inconclusive. It is important to recall that many of the older building traditions have persisted especially in traditional and rural places much longer than they have in other parts of the country. While it may be unlikely to see common bond anywhere before 1790 or so, it is highly likely that in some places English bond was used in the 19th or 20th centuries. In places where people are interested in historic architecture, these older building styles persist even until today in the work of restorers. It is always important to be cautious not to confuse historic building materials with high quality restorations or historically appropriate additions. For conclusive dating, we must always use several methods in combination for the most accurate results. If there are no written accounts existing recording the date a building was constructed (and even if there are, because it can be hard to know whether a historic building was destroyed and rebuilt unless there is a lot of documentation) the most certain method for dating historic buildings retaining original wood is dendrochronology, tree ring dating. It is possible to date many buildings within a year or so of their construction using this method. List of historic american brick bonds with approximate dates of use FLEMISH BOND - Prevalent from the 17th century until around 1815. It persist later and is still used on traditional formal buildings like courthouses. ENGLISH BOND - Used from the 17th century until around 1800 3-COURSE COMMON BOND - Used from around 1790 until about 1825 5-COURSE COMMON BOND - Used from about 1825 until the 1850's 6-COURSE COMMON BOND - Used from the 1850's onward 7-COURSE COMMON BOND - Used from the 1850's until present RUNNING BOND - Not used for structural walls. Its use could indicate newer construction with a brick veneer. It was used for small structures that didn't need to support much weight like the tops of chimneys from the earliest times. PORTLAND CEMENT AND MODERN BRICKS - Began around 1900 These dates may vary slightly from region to region and various other brick bonds may have been used in rare applications. This is a simple presentation of the brick bonds most common in historic Virginia. This article was written by Gananath Giri, Property Manager at Quietude in Hanover County, Virginia.
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