Cob: Introduction

[D.J. Henman]

Mick,

mick stone wrote:

> why is a concrete slab a bad idea for a foundation?

If there are other ways to reduce portland cement quantities used, the 
better off the world is and alternatives might save you money.

> i'm thinking for my future project in costa rica where summertime 
> rainfall is high that i will need to put in a concrete slab to get the 
> floor level of my house up a bit from the ground level which can 
> become soggy and drenched. is this not a good idea? 

I don't think you have to pour a slab floor just to rise.   There are 
other ways, since old times for stabilizing earth build upon.   Even 
road construction used earth stabilization packing a mix of  soil,  
lime, gravel, sand.    I suppose that the local people originally build 
the floors up high to let air floor under to keep cool as well.   These 
were probably on a post foundations. 

Foundations for a cob wall

It would be interesting challenge to design a cob structure with a 
raised floor.   The foundation and could be rock and cement for the 
cob.   You still might want to stabilize the ground around it.

It was a custom to do a soil/lime rammed earth path around the house to 
people could walk around it and not walk through mud.

Just some ideas for you.

Darel