[Cob] Mould on cob wall

[billc_lists at greenbuilder.com]

At 5:51 PM +0200 7/1/04, Jane Mondrup wrote:
>We have been building a small cob house for some months now, and 
>will soon be finished. For the last week or two it has been raining 
>quite heavily, and now some of the cob has begun to go mouldy - just 
>a little bit on the surface, but still, I do not like it. Moreover, 
>some seeds from the straw has begun to germinate.

Pliny Fisk of the Center for Maximum Potential Building Systems 
(http://cmpbs.org) tells a story of experimenting with straw-clay 
some years ago.  Folks here in the states had read about it, and at 
some point an expert from Germany was coming over to teach them more. 
Pliny and the gang got their hands dirty and built a test wall before 
he came, and were appalled to find that the seed in the straw was 
sprouting all over.  They then scraped the surface clean of all the 
growth before the German got there.

When they proudly brought the visitor out to see their test wall, the 
first thing he asked was "why isn't it growing"?

Turns out the growth helps in two ways:  it draws moisture out of the 
center of the wall, and it creates a network of roots which helps 
bind the wall together better.


That said, I don't know about the mold problem.



-- 
Bill Christensen
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