thanks @a4

Are Kenyans easy to change their altitude.How hard is it easy for intruders(thieves) to hit those cheap materials and penetrate inside the house ?Kama nyumba ya mabati ama bao

@Wendz. The math does not add up. A 80sq.m house will cost about 2.4m. At 60% of the ordinary house,the prefab should cost about 1.44m and not 700k. Beware of marketing gimmicks since the cost of the roof, finishes, plumbing electrical etc remain the same.

@wendz, most prefab technology only zero in on walling, which is like 10% of total overall construction cost. This means even 50% savings on walling will only make a very tiny overall reduction of costs since the rest of the elements i.e foundation, roof, windows, doors, finishes remain constant and make 90% of total costs,

@xsk, yes, but not for long since juja,kedowa and kilifi quarries are in the verge of drying out completely in the next 5 years. other forms of walling, especially prefab types, will then start playing centre stage as its done in usa, europe and china.

@jkmwatha, economies of scale will not allow for any savings if prefabs are used only for interior walls.

@kratos, its possible to construct a stone house with kes 20k per m2, same as prefab panel house cost. Its also possible to construct the same stone house with kes 50k per m2 eg runda, muthaiga type houses. Its all about comparison of apples to oranges/apples . Stone houses can also be constructed in 18 days depending on the size. Time reduction is a matter of prior planning by the developer i.e preparation for required skill set, materials and funds. A stone house structure costs around 9k per m2, same as prefab paneled house. Stone houses however, are more superior in terms of security, climate control , low maintenance etc.

@maricha, the boulders can be used for walling as below. Rongai Tuala area has abundant supply of such boulders.

i still think prefabs can replace masonary walls. How can i post a photo here. Think of stalls; guard houses, lodgings etc any structure that you would build using mabati; prefab is a better bet. A car dealer along Kiambu road opp Total petrol station at Ridgeways has used them and the costs+ look is encouraging.

@jkmwatha, compared to stone, prefab wall is more expensive, at kes 1800 per m2 compared with stone at kes 1,500 when plastered one side. For rental flats, the walls can be made of prefab but will require higher maintenance than stone due to being weaker hence prone to damage. Prefab walls are good for offices where there is less occurence for wall damage. In UK and most other developed countries, prefab is the cheapest material to build. Kenya is also headed there in the next 5 or so years once stone quarries dry up.