@gathige, you can contact Regina Keino on 0719438957, she deals with bio digestors. For those who come from the mountain region, you can refer her as Regina K to save yourselves from having to answer too many questions about the last name....

Thanks a4a. I will get in touch with her. I won't even try the second name as my pronunciation will betray me esp when saying on the phone" nataka kuongea na Ms K*

@A4Arch, how fair or otherwise are these prices for the Makao thing by HF http://www.housing.co.ke/makao-booklet/#page-1

Great. Ahsante.

Almost all upper floors in kenya are constructed using concrete, and i think the average cost of the same is around 2600/m2, why is timber shunned for the same, I am thinking even using the 6X2 timber for the joists at a span of say 400mm would nearly half that cost, plus reduced weight. @4Architect, you have done a cost analysis of concrete slab, si tafadhali ufanye ya mbao.