Riven oak clapboards were a very common materials in the 17th, 18th and 19th centuries and were used extensively for covering exterior walls, interior partitions in cellars or workspaces, and even on roofs in place of shingles.  Riven clapboards were, and still are, made by using an L-shaped tool called a froe (or frow) to slit an approximately four-foot long piece of wood into long, thin sections.