Cob: Re: earth floors

[Darel Henman]

>From buildings that I have seen lime or a lime-mud mix,lime-mud-fibre,
or lime-mud-fibre-glue, or lime-mud-fibre-oil will bond well with
earthen walls made of clay earth, sand with mixed in fibre such as cut
straw, hemp, etc..  The lower base should be keyed like anything else. 
Brooms with tough bristles can be used for this to leave carved in lines
for the next layer.

Is lime is not your category of "cementatious".

I've read that if rice straw (maybe otherkinds as well) is allowed to
ferment then mixed into the lime and let to sit for a few months more
the fermented cut straw is soft and bonds with the lime mud. 
Addiontionally fermented aged straw seems to produce a kind of glue that
aids in water resistence and applicability.  This is normally used for
middle and finished coats over a rougher mud/straw wall.

Darel

"SANCO Enterprises, LLC" wrote:
> 
> Carla,
> When applying cementitious material to earth
> or straw, there is a natural bond break between the materials--they simply
> don't want to bond together.  Straw has more keying points and will allow
> the stucco or plaster to get a better grip.  Cob would be second best as you
> have a very uneven and rough surface to work with.
>