Re-using Cob?

[Will Firstbrook]

Hi Speireag & Shannon,

I would think you could soak it in a big pit for a week or so even with a
lot of water, then mix it in with fresh cob. Sure some of the straw is
cut-up and rewetted, but mixed in to a batch with fresh ingredients it
should be fine.

Ianto Evens of the Cob Cottage Co. mentioned the 500 - 300 year old cob
houses in England used very bad straw as straw was used more in those days.
The houses ended up with straw that the animals have used or floor sweepings
2" long. 

Good luck on your renovations.

Regards, 
Will

>On Wed, 30 Jul 1997, Speireag wrote:
>
>> Hallo all.
>> 
>>     We will be building our house in sections, and part of the construction
>> may involve taking down interior (non-load-bearing) cob walls as we adjust
>> the use of our interior space.
>> 
>>     Is cob re-usable?  If we knock it to pieces, put it in the mixing spot,
>> jump up and down on it, wet it down, and mix it, will we have cob?  Will
>> the straw survive two wettings?  Or does the ex-cob wall become backfill
>> someplace where we don't want drainage?
>> 
>> -Speireag.
>
>I've never head of anyone trying this with fully dried cob, my greatest
>concern would be that if you simply "break" it up, I would expect that you
>are going to break alot of the straw fibers which would make the new cob
>weaker due to shorter fibers.  My guess is that it would be alright if you
>broke it into some large chunks (as big as one or two people could carry),
>and then let the chunks soak in water in a covered pit (this might take
>days or weeks since you don't want to add to much water, but it would
>need to soak completely through all of the chunks).  At some point if
>it has soaked up enough water, you should be able to start breaking it up
>and working it without breaking all of the straw fibers.  I don't think
>there is much danger of damage to the straw from wetting it for reuse,
>since it is heavily coated with clay and sand which should help to protect
>it from decay.
>
>Of course I'm only guessing ...  Care to volunteer to collect the
>experimental evidence and report back :-)
>
>Shannon Dealy
>dealy at deatech.com
>
>