Cob: alternative materials/additives.

[Darel Henman]

Has anybody out there used or heard of the use of any of the following:

	1.) nut shells, i.e.,  almonds, peanuts, wallnuts, or even larger
coccunut pieces
            These I guess would most likely be used like wood chips or
saw dust in "sawcrete".
	    Maybe call it nutcrete.    Or they should be able to be used in a
light clay instead of
            wood chips.
  
	2.) hair (human or animal) I suppose this would mainly be for fibre in
clay-mud plasters

	3.) feathers (the middle hornish material stem part is, I believe
airtight which would add to
            thermal resistance.  
		a.) could use as additive to cobs, or cement?
		b.) used as is in-between walls or ceiling for insulation?
                    Maybe they could be coated with someting is they are
inflamable.

        4.) Charmaine mentioned, if I remember correctly, that rice husk
ash can be used with lime to
            make a possible stronger natural cement.  


Also below is an excert for forests.org about an old waterproofing
method used in Russia for earthen dams.

A biological resulting material called:  "GLEY"  
Below is an excert from: URL: 
http://forests.org/ric/good_wood/nont_bld.htm#anchor556637

"Related to the word 'glaze', a gley is like a biological plastic
membrane such as is found in bogs, which is formed by a bacterial
process that requires anaerobic conditions.

Traditionally a technique for sealing ponds and dams, there is potential
for the process to be adapted for human-made structures. The
Russian-devised version for dams uses a slurry of animal waste (pig
manure) applied over the inner base and walls of the dam in multiple,
thin layers, which is then itself covered with vegetable organic matter
such as grass, leaves, waste paper, cardboard, etc. This is all then
given a final layer of soil which is tamped down and the mixture is left
for several weeks to allow the (anaerobic) bacteria to complete their
task, at which time the dam is ready for flooding.

Gleys have the potential to revolutionise water storage capacity in
regions with hightly porous soils. An aquaculture industry in otherwise
unsuitable areas scould be one of the benefits of this technique. 

Unlike bentonite clay, gley materials are virtually cost-free and are
comprised of 'wastes' which would normally be discarded in the normal
course of operations. Also, plastic and rubber dam liners may actually
be dependent on the same anaerobic process for their own continued
effectiveness rather than their lack of holes or punctures ュ ie, it is
the anaerobic layer created below them rather than their own membranous
qualities which prevent water seepage in the long term. "
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Darel