People who live in older houses sometimes wonder about the history of their house. When was it built? What did it look like when it was first built? Who lived in it previously? For some homeowners these questions are a matter of curiosity. But others are interested in restoration, and they would like historical information to recreate the architectural authenticity of their houses.
To begin, walk around the house and look carefully at the details. Are the walls plaster or wallboard? Wallboard was introduced into residential construction around 1950. Houses with plaster walls generally predate that. Look at the wall switches. Very likely these have been updated with modern pieces, but there may be an older, antiquated switch possibly in an attic or utility room. There may be, for example, a push-button wall switch, which were widely used from 1920 to 1940. An even older style of wall switch was the rotary-snap switch. The presence of one would indicate that the house was built between 1900 and 1920.Continue in the attic and cellar. Measure the studs, joists and rafters. Before World War II, construction lumber was dimensionally accurate, that is, a 2x4 was 2 inches by 4 inches. Modern construction lumber is dressed so that 1/4 inch is planed off each side. Today's 2x4 is actually 11/2 inches by 31/2 inches. The presence of dimensionally accurate lumber indicates that the house was built before World War II.
Next, examine the surface of the wood for saw marks. In most cases any saw marks will be the curved, arclike tracks of a circular saw. The circular saw was introduced as early as 1830, but it was not widely used until the end of the century. It is likely then that the board was cut in the 20th century.
Sometimes the marks will be a series of evenly spaced straight lines. These are the distinctive tracks of a reciprocating, or up-and-down, saw. If the beams have reciprocating saw tracks, they were probably cut sometime in the last century.
Very old beams may have straight saw marks in an unevenly spaced, zigzag pattern. Those timbers were probably cut in the 18th century by a two-man team using a pit saw.
Saw marks can give you a rough idea of when the wood was cut. That, however, does not mean that your house was built at that time. It is possible that the lumber was used to build a house that was later demolished. A thrifty carpenter could have salvaged the wood. It is important then to gather additional information.
Examine the nails used to hold the wood together. Houses built in the 18th century have handwrought nails, and also wood pegs. The nails have square or rectangular shafts that taper to sharp points. Because each nail is forged by hand, no two are identical. Between 1790 and 1830, the cut nail with the handwrought head was introduced. That nail has a uniform rectangular shaft with a roughly rectangular head. By 1830, cut nails with machine-forged heads were introduced. They were used to build most houses in the 19th century. By 1890 the cut nails gave way to the modern wire nail. Wire nails have round shafts and heads and are common in all houses built in the 20th century.
The earliest construction was timber frame, sometimes called post and beam, construction. The house was framed with massive beams that were held together with carefully carved mortise-and-tenon joints. Timber-frame construction was used from colonial times through the Civil War. It was replaced by balloon-frame construction. In that method the wall studs extend from the foundation to the roof. The floor joists were then nailed to the studs. At the turn of the 20th century platform framing became the most widely used method of residential construction. In platform construction the individual stories are built separately, one on top of the other.
It is relatively easy to recognize timber-frame construction by examining the exposed framework in the attic. It is almost impossible to distinguish a balloon from a platform frame unless studs near the first-floor ceiling are exposed. Sometimes it us possible to study the structural details if the walls are open for repairs.