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Roof Support
The roof needed to span excavation, support soil covering, resist snow load and wind stress. This required substantial structural support—typically central posts supporting roof beams, with rafters extending from center to excavation walls.
The central posts were largest, strongest timbers available—sometimes entire tree trunks, stripped of branches, set deeply into floor for stability. Secondary posts around perimeter provided additional support. The beam and rafter system distributed weight across these supports, transferring loads to ground rather than relying solely on excavation walls.
Roof Construction
The roof structure was covered with materials providing weather protection while allowing insulation. Typical sequence was poles or branches laid across rafters, then bark or hide covering providing water barrier, then sod or earth layer providing insulation and final weatherproofing.
The sod covering could be substantial—a foot or more thick, providing excellent insulation, blending structure into landscape, eventually growing grass on surface so roof became indistinguishable from surrounding ground. This living roof required no maintenance, improved with age as plants established, added structural integrity as roots bound soil together.
Smoke hole was left in roof center—allowing smoke from hearth to escape, providing some light entry, creating ventilation. The hole could be covered partially in severe weather but needed to remain open enough for smoke escape or interior became unlivable.
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