[Cob] floors before walls

[Shannon Dealy]

On Wed, 23 Jul 2008, Tys Sniffen wrote:

[snip]
> floors are the drain rock/gravel. and since the sun is hot, making cob
> inside, under the roof, seems like the way it will go.
[snip]
> practice, so you're not beating them up during construction. but since I'm
> probably going to be doing 3 or 4 layers (including the radiant heat tubes)
> why not put down one layer before starting the cob walls, to give myself a
[snip]

Tarps leak, so mixing inside over your drain rock (or just on the bare 
compacted ground) is going to be constantly wetting the earth below and 
that will be a problem later on when you are doing your floor over 
that area since the moisture you added to the earth below will be trying 
to come back out (learned this the hard way).  Doing the base layer of 
your floor over the drain rock before doing the walls should be fine, 
providing:

   - the layer is thick enough to protect the radiant heat tubes

   - strong enough to hold up to the work you do on top of it without
     breaking up

   - Not getting wet constantly from cob mixing on top of it

   - Has dried out enough to take the abuse before you start working over it.

Your base layer of cob is just a rough surface anyway, so having the top 
of it beat up is not a big deal since there will other layers on top of 
it, but you still need it to be strong enough to take the abuse without 
getting pushed down into your drain rock, or having sections of it come 
apart.

FWIW.

Shannon C. Dealy      |               DeaTech Research Inc.
dealy at deatech.com     |          - Custom Software Development -
Phone: (800) 467-5820 |          - Natural Building Instruction -
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