Concrete slab on ground, strip footings, or piers which can be timber, concrete, steel or masonry and bearers are all options. The width of foundations should be governed by the width of the walls.
A 200mm thick hemp masonry wall using the Australian Hemp Masonry Company’s mix guide is 146 kg/sqm; this is comparable to the weight of a single skin of brickwork.
A damp proof course should be used at the base of the Hemp walls to prevent rising damp, as with any other kind of masonry construction. This is important to ensure the satisfactory long term performance of the walls. It is also important to make sure that applied finishes such as sheets or renders do not bridge this impermeable separating layer.
As advised with all construction, the ground should be sloped away from the base of Hemp walls, to ensure walls are kept dry.