[Cob] insulation

[Bernhard Masterson]

Roselle writes:

>I am very interested in cob, and one hurdle I'm trying
>to overcome is the issue of insulation in cold
>climates.  I just heard of someone locally who just
>tore down a cob building because it was a major cold
>sink.  I'm in the san juan mountains of colorado.

>I've read ideas of outsulating on this list.  It
>sounds like it has too many problems. Has anyone tried
>insulating from the inside?

As long as you have good southern exposure for solar gain I believe that a 
bale-cob building would be excellent and may need almost no additional heat 
source in the San Juans.  If you do not have good access to the sun I 
wouldn't recommend cob.  Building an integrated wall of cob and bale with 
bale on the outside will provide you the thermal mass in cob to not overheat 
from the sun since the heat will be stored in the cob and released at night. 
   The insulation of the bales will keep the heat in wonderfully.  A good 
couple of inches of plaster on the bales will provide them plenty of 
protection in dry CO.  See one of the recent Cob Web newsletters for more 
info. on bale-cob.
    I built my house using bale-cob here in Portland, Oregon.  On our 
coldest cloudy days of 20-30 degrees with wind we loose seven degrees over 
24 hours if we don't run our rocket stove at all.  On sunny days of the same 
temps. we do not need to run the stove at all since we get plenty of heat 
from the sun and our south facing windows, dark cob floors, and trombe wall.

- Bernhard
_________________________________bernhard_masterson at hotmail.com