The Pamoja prototype for affordable housing has a shell of pre-formed, galvanised and pre-finished sheet steel, bolted to precast concrete foundations. No timber is used (in deference to Kenya's deforestation crisis). Instead, internal elements such as partitions and shelving are made of locally produced recycled compressed fiber. Internal walls and ceilings are coated in manually sprayed pumice insulation, with an applied paint finish. Variations of the prototype house have been developed to take into account climatic, social and cultural differences.