njokimugo wrote:LxWxH 25cm x 12.5cm x 7.5cm
This translates to 0.25m by 0.125m by 0.075m.
The side surface is 0.25m x 0,075m=0.0185m2
I m2 of brick surface costs as below.
0.0185m2 =kes 21.5
1m2=21.5/0.0185=kes 1,146kes.
A machine cut stone is 0.4m by 0.2m by 0.2m.
The side surface is 0.4m x 0,2m=0.08m2.
Im2 of stone surface costs as below
0.08m2=kes55
1m2=55/0.08=kes 687.
Stone is approximately 70% cheaper than the brick.
For earth bricks to rival stone, they need to advance from wall into wall + roofing material like the ancient Nubians used to do. This way, cost of roof timber trusses and roofing sheets is completely removed.
http://www.lavoutenubienne.org/en/nv-techniqueAs Iron Sharpens Iron, So one Man Sharpens Another.