Single storey buildings in Kenya can be constructed using various technologies to reduce construction cost such as using stone, prefab panels or earthbags.
Cost of construction of asingle storey building can easily be reduced by having small reduction costs in all the building elements i.e foundation, walling, roofing, doors and windows and finishes.
Stone is increasingly becoming expensive as quarries dry up in Juja. Cost of walling with cost per m2 of stone wll surface with one side plastered at around kes 1,400 per m2. This is slightly cheaper than prefab walling at kes 1,800 per m2 but more expensive than earthbag walling at kes 800 per m2 with both sides plastered.
Stone has advantages in that it does not require external plaster and is self supporting.
Cementous prefab panels cost a minimum of kes 1800 per m2, higher than stone wall and earth bag walling. They also require light steel gauge structure to support .
Prefab panel advantages are that the panel is usually quite smart since the plaster is done in factory controlled confines, hence the accuracy.
This is self supporting and provides the lowest cost ossible for single storey walling compared to stone, iron sheet and prefab panels.
The disadvantage is that the wall is 450mm thick, hence not suitable for small spaces since the wall takes up large floor area surface.
Bottles can be introduced to create interesting wall patterns.
Francis Gichuhi Kamau, Architect.