Concrete footings are laid 9" (23cm) deep in a 1m wide trench. The first 1' (31cm) of wall above ground should be built with impervious stone followed by cob blocks: 18" (46cm) wide to the required height.

Walls should be topped with slate or clay tiles, capped with clay ridge tiles, or thatched, according to local style.
A section of wall 1m x 1m by 46cm deep requires 40 blocks. One tonne of mortar is enough for 200 blocks. Mortar is made of 4 parts of lime putty to 1 part of coarse sand. A scratch render coat is flicked on and the second coat is roughly trowelled on.