Cob

Cob is a traditional building material made by mixing subsoil, water, straw and sometimes sand into a stiff, workable mass that is built up in courses by hand without formwork, unlike rammed earth, which is compacted into forms, or adobe, which is cast into unfired bricks. Its thermal mass helps moderate indoor temperature in hot-dry climates, and its thick, monolithic walls, load-bearing without additional framing, have produced vernacular buildings in England's West Country, parts of Africa and the American Southwest that have survived for centuries when properly protected from standing water by a wide roof overhang and a raised stone foundation.