Civil Engineering and Building Technology

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CIVIL ENGINEERING AND BUILDING TECHNOLOGY

The decades surrounding the American Revolution, from the 1760s until about 1820, saw few advances in building technology. Where change occurred it was often small, local, and incremental. The buildings of the early nineteenth century look different from their colonial counterparts, a product of new republican sensibilities that stripped down the ornate detail of the classical Georgian style and replaced it with the simpler lines of the Federal style. Despite the change in appearance, though, buildings of the new American nation were constructed with the same traditional techniques that had been in use for generations.

building materials

The availability of timber and the early development of sawmills made wood the construction material of choice in early America. By the mid-eighteenth century, standardized conventions for size and quality of lumber facilitated long-distance transactions, and a complex system of sawyers, agents, and board yards moved wood from timber lot to the towns and cities where construction was taking place. Most builders fashioned their buildings from quick sketches and traditional mental templates, substituting creativity, intuition, and experience for more formal written drawings and designs. In the 1760s architectural design books from England became available in the colonies and encouraged a greater level of uniformity and standardization in high-style elite urban buildings. By the 1790s the patterns were being used by tradesmen of all classes, and English architectural conventions increasingly influenced vernacular building techniques and designs in the countryside as well.

Most wooden structures were framed with heavy hand-hewn posts and beams joined together by hand-carved mortise-and-tenon joints, covered over with sheathing and clapboards and roofed with hand-split wooden shingles. Frames were often fit together into subassemblies at the mill or carpenter's yard, then marked, disassembled, and shipped to the building site. At the site, builders would reconstruct the subassemblies, then supervise the raising, in which local townspeople would come together for a day to pull the sides up into place and attach the roofing frame. Raising a frame was dangerous business, so it was important that all involved understood how the framing was supposed to go together. Consequently, the house-raising tradition worked against innovations in framing. With advances in sawmill technology in the 1790s, sawn framing members increasingly replaced hewn timbers and helped fuel the building boom of that decade. Machine-cut nails, a cheap alternative to the hand-forged nails that had been in use for centuries, also became widely available in the first decade of the nineteenth century. The availability of both sawn lumber and nails resulted in a more economical braced-frame style of construction, which replaced some of the heavy timber framing with smaller, standardized studs attached by nails rather than hand-carved joints.

In the mid-Atlantic and the South, a significant amount of brick construction took place, particularly in cities like Philadelphia and Baltimore, where bricks were used to build whole blocks of residential row houses. There were few brick structures in the Northeast, largely due to the lack of the limestone that was necessary for both mortar and plaster. The exception was in chimney construction, where brick was in use everywhere from the late seventeenth century. Brick vaults, which had replaced rubble-stone foundations beneath chimney stacks by about 1800, provided both a stronger foundation and a built-in cellar storage area. Brickmaking was an ancient art, and this period saw few departures from the traditional production process, the only real innovation coming in 1815 with the burning of anthracite coal and wood in the kilns. The combination created slightly inferior bricks and mortar but greatly reduced the time and cost involved.

Most eighteenth-century foundations were constructed either of packed earth or loosely fitting stones and boulders bound together by mortar. In the 1790s improved quarrying and splitting techniques allowed builders to cap foundations with hewn granite slabs that greatly enhanced durability and stability. Techniques for milling and cutting stone were also perfected in this decade, resulting in the increased use of granite and marble for both structural and decorative purposes.

industrialization and transformation

The 1820s and 1830s witnessed a dramatic transformation in building technology. Sawmills began to replace old up-and-down saws, which only cut on the down stroke, with the new and more productive continuously cutting circular saw. As a result, sawn frames, shingles, and lath for plaster all became much more inexpensive and widely available than their hand-fashioned antecedents. Steam-driven sawmills began to free sawyers from their dependence on seasonal water flow. New nailheading machinery made cut nails even more economical, and the invention of planing machinery greatly reduced the time and skill necessary for sizing boards and producing finish work. Carpenter-builders shifted from the scribe rule system of measurements, where individual framing members were trued up and fitted with respect to each other, to the square rule, which emphasized standardization and the interchangeability of framing elements. These technological developments, coupled with the need for fast and cheap construction on the expanding American frontier, led to the invention of balloon-frame construction. First used at Fort Dearborn, near Chicago in 1833, the balloon frame replaced the posts, beams, and braces with rows of smaller, lighter studs, rafters, and joists, wholly held together by nails rather than hand-carved joints.

Steam machinery facilitated hoisting and cutting operations in quarries, and slate became an increasingly popular roofing material, particularly in cities, where wood-shingled roofs had proven to be dangerous fire hazards. Mechanized brick making, the use of poured cement in construction, and iron-framed structures all began to appear in the late 1820s. The development of practical cast iron stoves in the early 1830s freed builders from the limitations on floor plans imposed by the earlier need for a fireplace in each room. More choices were available to builders, but the technology and the construction practices of the 1820s and 1830s were also transforming building from a traditional craft trade into a factory-style operation. Though in many places, particularly in the countryside, vernacular and hand-crafted building practices continued for much of the nineteenth century, the industrialization taking place at the end of the early national period produced more efficient and standardized building technologies that fit the needs of the rapidly growing nation.

See alsoArchitecture; Housing; Technology .

bibliography

Condit, Carl W. American Building: Materials and Techniques from the First Colonial Settlements to the Present. 2nd ed. Chicago: University of Chicago Press, 1982.

Garvin, James L. A Building History of Northern New England. Hanover, N.H.: University Press of New England, 2001.

Larkin, Jack. The Reshaping of Everyday Life: 1790–1840. New York: Harper and Row, 1988.

McAlester, Virginia, and Lee McAlester. A Field Guide to American Houses. New York: Knopf, 2000.

Rilling, Donna J. Making Houses, Crafting Capitalism: Builders in Philadelphia, 1790–1850. Philadelphia: University of Pennsylvania Press, 2001.

David R. Byers

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