[Cob] Cobhouse Design

[howard at earthandstraw.com]

We have taught and built many straw bale buildings over the years but I learned the most about plasters when I tore one down.  It was a small experimental building that we had tested many plaster recipes on at the Ecovillage Training Center, beginning with straight earthen plasters, mixed with various fibers, some mixed with sawdust, then some lime/clay and on to full lime plaster.  What I learned was that the lime and lime/clay plasters surface bonded the bales together but the all earthen plasters did not.  I could bang the earthen plasters off with a sledge hammer just ramming the wall knocking all the plaster off but when I got the lime/clay plasters I had to go to full swings with the hammer and do so along the course lines in order to break the bale out of the wall.  It became a lot of work on the lime and lime/clay portions of the building.  I recommend lime or lime/clay plaster for the first two coats on bales to protect them from insect or rodent infestations then what ever you want for a finish coat.


Howard Switzer, Architect
668 Hurricane Creek Road
Linden, TN 37096
931-589-6513
www.earthandstraw.com