Listen to this wisdom:
Walling
The cave man noticed after threshing corn that straw mixed with earth makes big lumps which hold together. The earth molecules do not hold together enough so we have to have a stabilising factor. The straw mixed with mud at harvest time showed man how to make mud bricks, Adobe, to build walls.
Roofing
When he came to the problem of roofing primitive man used timber or other materials. But timber was not always at hand.
In Iran, Egypt, Libya and Tunisia they found a solution. If you build a boat, every ring is pulling on the other, and it is working entirely under tension. There is no compression or it would crumble. If you reverse this upwards it will be working entirely under compression. Mud brick can take compression but not tension.
They invented a system to build roofs with just bricks end to end, leaning the vertical a little against an end wall so that the brick is on an incline plane.
The sticking power is the weight of the brick multiplied by the cosign of the angle divided by the area of the brick. They found that they had to have very light adobe bricks, 25 cm by 15 cm and only 5 cm thick.
- Hassan Fathy,
#MjengoElimu
We are bringing back this style of building. The greatest mistake the African did was to reject his own technology for building.