Cob Curious

[John Schinnerer]

Aloha,

> -----Original Message-----
> From:	Grace Benjamin [SMTP:grey_sea at hotmail.com]
>First; foundations...Around the 
>perimeter of the house, I would dig 3ft wide holes down below the freeze 
>line, ...

You might want to look at info on frost-protected shallow foundations:

http://www.oikos.com/esb/43/foundations.html

...as a way to avoid needing to excavate down below frost line.  The info is
based on "industry-standard" poured concrete foundations, and does involve
the use of rigid foam insulation, but it's pretty easy to extrapolate the
basic principles to less concrete-intensive methods.

>I would then tie the whole wall and pier structure together with a single 
>concrete bond beam, poured both over the wall and the piers.  The cob walls

>would then sit on top of the bond beam.  

You'll want to make sure the top of your foundation is not smooth and not
sloping away from center - make it rough and uneven, embed some pointy rocks
and/or rebar, etc. that stick out so the cob will have lots of "teeth" to
grab onto when it is laid on.

>Second; design.  I have this notion of "whole-house" design, where the
house 
>is a machine, and with proper maintenance could theoreticaly last 
>forever...

I prefer to consider the whole house as a living organism (which I am part
of) rather than a machine... :-)

>The first 
>floor will be cob for thermal heat retention, and the second floor Straw 
>Bale for insulative heat retention.  

Note that warm air rises, so if the cob is the first floor it won't absorb
as much heat from the first floor air as it would from (warmer) second floor
air.  This may be just fine, depending on your climate...but for example, if
"too warm" is a problem some parts of the year, this design would hold "too
warm" air in the upper part (due to SB as insulation) and the cob below
wouldn't be tempering the heat by absorbing it from that warm air up
above...

John Schinnerer