The walls of the building are plastered in earth using wheat paste
to improve the workability and provide strength and adhesion.
Pictured (right) you can see sample patches of plaster to test
various earth mixes on
the exterior cob walls. Many samples were made to test the hardness
and durability using lime, linseed oil, cactus juice with
different mixes of soils and animal dung. See the video right.