[Cob] Soil Survey

[Shannon Dealy]

On Tue, 28 Jul 2009, yewberry at wavecable.com wrote:

[snip]
> A high percentage of silt (I'm pretty sure 30% constitutes "high") will 
> greatly weaken your cob mixture.  I don't know of any real way to remove silt 
> from a large amount of soil.  Better to find another source, I'm guessin'.
[snip]

There is no substitute for actually testing the mix.  The soil at my 
place works just fine for cob even though the silt is around 35%.  While 
silt does interfere with the bonding of clay, lots of clay or lesser 
amounts of very sticky clay may make up for it.

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