[Cob] Windows in Cob Wall

[Shannon Dealy]

On Wed, 5 Oct 2016, Bill Wright, L.Ac., DNBAO wrote:

[snip]
> I'm not totally clear about your statement, "Caulking or other sealants
> would be useless as the water will come in around it through the
> plaster". It's confusing to me because the outside of the building has a
> lime render over the cob. I understand that lime, "breathes", but I
> understand that it also acts to keep water out for the most part;
> functioning more to allow the transpiration of water, and not the actual
> transportation of water. Is this your understanding/experience?

Hi Bill,

Think of cob and to a greater extent, lime render, the way you would a 
"water resistant" rain coat. It sheds most of the water, most of the time.
Any rain will likely soak into the surface a little bit, a prolonged 
period of rain/drizzle with little or no drying time will soak in more, 
getting in around your caulking. It is however, unimportant as the cob 
will wick these low levels of moisture away from the surface, distributing 
it throughout the walls of the building. The amount of moisture that will 
enter your cob by this means is extremely low relative to how much is 
required to have any significant structural effect on the cob, and it will 
dry out when the weather becomes warmer/dryer in Spring/Summer.

For what it's worth, my buildings have never had anything other than bare 
cob on the outside (not by design, once they are functional, I find 
that I'm just to busy to do more work on them). They get some areas of 
minor errosion, but not enough for me to feel the need to do anything. 
I believe all of them are now over 10 years old. Of course, I been 
out of the country for 14 months, so maybe they have all fallen down 
:-)


Shannon C. Dealy            |         DeaTech Research Inc.
dealy at deatech.com           | - Biotechnology Development Services -
Telephone:  +1 541-929-4089 |        USA and the Netherlands
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