The typical residence of both the northern and southern Sioux during the Middle and Late Woodland Period (200 BC 900 AD) was the round pit house. It was the progenitor of both the Mandan earth lodge and the Great Plains teepee. (See articles on the teepee and the Mandan earth lodge.) It was a stoutly built, heavily insulated structure that would keep its occupants comfortable in both extreme heat and bitter cold.
To build a pit house, the Siouan first excavated a round depression in the landscape about 12-24 inches deep. Wood posts, from 3-6 inches in diameter, were imbedded around the periphery of the depression about 3-5 feet apart. Saplings or river canes were interwoven like basketwork between the posts. Wet clay was then pressed against the lathing to make it air tight. Posts were usually embedded outward from the planned entrance to the house about 3-5 feet. These would be the support for a covered entrance. Afterward, earth was dumped against the walls of the house to form a berm, which would insulate the occupants from temperature extremes.
Once the wall had been braced by the earth berm, a conical, teepee-like roof frame was constructed how of small tree timbers. Saplings were then lashed to the timber girders to form purlins. Vines and small sapling were then interwoven between the timber girders and the purlins to tie together the structure. Either thatch or tree bark shingles were then tied to the roof framework to shed off rain water.
The hearth of the pit house was usually in the center of the floor. It was formed by digging a little deeper into the floor, surrounding that depression with small stones, and then coating everything with clay.
The lifespan of the Siouan pit house varied with its location. Northern Siouan structures might last ten to fifteen years if the roof remained intact. Southern Siouan pit houses in warm, humid locations could last on a few years because of wood destroying diseases and termites.