Subject: Re: "Cob" Construction

From: Richard Austin <[email-masked]>
Date: 31 Jul 1995 14:57:31 GMT

The process is very simple, you can start experimenting with it now.
It reached its peak use in Germany I think. (It is still widely used 
there and has been for hundreds of years). Here's how to do it.

1. Get some straw and put it in a pile.
2. Mix clay to the consistency of a milk shake with water.
3. Pour the "milk shake" over the straw, tossing with rakes or 
pitchforks until just lightly coating the straw.
4. Place in between boards and tamp with a 2x4 or 4x4. (about 3-4 ft. 
long)
5. Move the boards up immediately and stuff some more.
6. Allow the wall to dry. (Time varies by climate)
7. Plaster inside and out with soft plaster
8. Use a water resistant plaster on the outside.

The clay is not too critical, anything from 40-50% clay soil all the way 
up to all clay will work (at least in my experiments). You don't need to 
add sand. Save the sand for the plaster.

Mostly post and beam construction is used and boards on each side of the 
posts make up the "form" to stuff the staw-clay into. Walls can be 6 
inches to 18 inches or more, thick walls take longer to dry. 

That's about it.

I like this approach. It is superior to staw-bale. The only problem is 
that roofs are still expensive. I am working on a system that allows the 
straw-clay system to make domes and build the roof at the same time from 
the same material. Then you can really reduce the cost of housing. Just 
ferrocement in inner and outer shells and you have a really strong 
structure!

Richard Austin  --  email: [email-masked]  --  radio: KG7SU
-------------------------------------------------------
              Institute for Planetary Renewal
"Creating a Better World Through Healing & Design"

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From: Richard Austin <[email-masked]>
Date: 31 Jul 1995 14:58:58 GMT

That's about it.

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From: [email-masked] (AWarch)
Date: 11 Aug 1995 21:24:41 -0400

Robert LaPorte of the Natural House Building Center, Fairfield, IA
(515)472-7775
offers workshops in straw/clay construction and natural plastering. Good
luck.