The History of Building Construction ( The Stone Age)
Primitive building The Stone Age
The hunter-gatherers of the late Stone Age, who moved about
a wide area in search of food, built the earliest temporary shelters that
appear in the archaeological record. Excavations at a number of sites in Europe
dated to before 12,000 BC show circular rings of stones that are believed to
have formed part of such shelters. They may have braced crude huts made of
wooden poles or have weighted down the walls of tents made of animal skins,
presumably supported by central poles.
A tent illustrates the basic elements of environmental
control that are the concern of building construction. The tent creates a
membrane to shed rain and snow; cold water on the human skin absorbs body heat.
The membrane reduces wind speed as well; air over the human skin also promotes
heat loss. It controls heat transfer by keeping out the hot rays of the sun and
confining heated air in cold weather. It also blocks out light and provides
visual privacy. The membrane must be supported against the forces of gravity
and wind; a structure is necessary. Membranes of hides are strong in tension
(stresses imposed by stretching forces), but poles must be added to take
compression (stresses imposed by compacting forces). Indeed, much of the
history of building construction is the search for more sophisticated solutions
to the same basic problems that the tent was set out to solve. The tent has
continued in use to the present. The Saudi Arabian goats’ hair tent, the
Mongolian yurt with its collapsible wooden frame and felt coverings, and the American
Indian tepee with its multiple pole supports and double membrane are more
refined and elegant descendants of the crude shelters of the early
hunter-gatherers.
The agricultural revolution, dated to about 10,000 BC, gave
a major impetus to building construction. People no longer traveled in search
of game or followed their herds but stayed in one place to tend their fields.
Dwellings began to be more permanent. Archaeological records are scanty, but in
the Middle East are found the remains of whole villages of round dwellings
called tholoi, whose walls are made of packed clay; all traces of roofs have
disappeared. In Europe tholoi were built of dry-laid stone with domed roofs;
there are still surviving examples (of more recent construction) of these beehive
structures in the Alps. In later Middle Eastern tholoi a rectangular
antechamber or entrance hall appeared, attached to the main circular
chamber—the first examples of the rectangular plan form in building. Still
later the circular form was dropped in favor of the rectangle as dwellings were
divided into more rooms and more dwellings were placed together in settlements.
The tholoi marked an important step in the search for durability; they were the
beginning of masonry construction.
Evidence of composite building construction of clay and
wood, the so-called wattle-and-daub method, is also found in Europe and the
Middle East. The walls were made of small saplings or reeds, which were easy to
cut with stone tools. They were driven into the ground, tied together laterally
with vegetable fibers, and then plastered over with wet clay to give added
rigidity and weatherproofing. The roofs have not survived, but the structures
were probably covered with crude thatch or bundled reeds. Both round and
rectangular forms are found, usually with central hearths.
Heavier timber buildings also appeared in Neolithic (New
Stone Age) cultures, although the difficulties of cutting large trees with
stone tools limited the use of sizable timbers to frames. These frames were
usually rectangular in plan, with a central row of columns to support a
ridgepole and matching rows of columns along the long walls; rafters were run
from the ridgepole to the wall beams. The lateral stability of the frame was
achieved by burying the columns deep in the ground; the ridgepole and rafters
were then tied to the columns with vegetable fibers. The usual roofing material
was thatch: dried grasses or reeds tied together in small bundles, which in
turn were tied in an overlapping pattern to the light wooden poles that spanned
between the rafters. Horizontal thatched roofs leak rain badly, but, if they
are placed at the proper angle, the rainwater runs off before it has time to
soak through. Primitive builders soon determined the roof pitch that would shed
the water but not the thatch. Many types of infill were used in the walls of
these frame houses, including clay, wattle and daub, tree bark (favored by
American Woodland Indians), and thatch. In Polynesia and Indonesia, where such
houses are still built, they are raised above the ground on stilts for security
and dryness; the roofing is often made of leaves and the walls are largely open
to allow air movement for natural cooling. Another variation of the frame was
found in Egypt and the Middle East, where timbers were substituted for bundles
of reeds.
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