Cob lime-stabilized cob

[Michael Saunby]

> Hi everybody,
> 
> from many sources I learned that lime can be used to stabilize adobe, rammed earth, etc. with a clay content of at least 20%. So it should work with cob as well, right? Or am I missing something?
> 
> Uwe
> 
> 
At the traditional building repair course  I attended here in Devon last 
summer lime putty was added to the cob that we made.  How useful it is I 
don't know since the proportion used is likely to be very small, I also 
doubt that it was added traditionally.  

One traditional use of lime that I've found works well for me is to make 
plaster from earth, lime, and sand to give a breathable but weather proof
external coating.  It dries very hard but is still close enough in
its make up to the cob that it doesn't crack off.  The plaster should 
really have animal hair added and then be finished off with a few coats 
of limewash (add soil or pigments for colour).

-- 
Michael Saunby
Teachmore Farm, Jacobstowe, Okehampton, Devon, United Kingdom. EX20 3AJ