[Cob] Mix

[Shannon Dealy]

On Sun, 18 Jul 2010, Janet Standeford wrote:

> Can anyone tell me how much cob, by foot measurement, that one bale of straw 
> weighing 110 lbs should make?
>
> BTW one of our projects this year if enough people show up will be a cob 
> cistern.

Cob is typically about 10% straw (by volume), assuming your bales are 
comparable to mine, your 110 lb bale is probably about 10 cubic feet of 
straw which works out to (very roughly) 100 cubic feet of cob.  This of 
course assumes a typical mix, some people push the straw content 
significantly higher for special purposes, and some people don't put 
enough straw in the mix.  If you are trying to figure out how many bales 
you need, get a number of extras.  There is not only variations in the 
mix to consider, but they also make good places to stand on as the 
wall gets higher, and can be stacked like bricks as the wall height 
increases.

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