Cob in cold climes

[Renewables at aol.com]

Will,

Yeah, we're looking forward to seeing your sb home pictures.  What is your
target timeframe for leaving the city for good to move into the sb home?  The
kids grow up so fast you may not need much of a bigger house by the time you
get around to building the cob castle.  Is your area pretty rural or is it
close to many weekend homes from city folks?  What is you soil type like
there?  I seem to find the two extremes wherever we look, never anything close
to use as-is.  I can now see the value of not hauling much of any material to
the building site if possible.

We had unknowingly made a cob brick last fall.  Our son was doing a project
for his social studies class.  Extra credit could be had for bringing in an
adobe brick (represented as a basic building block in many countries).  Of
course he came to me at the last minute, so I didn't have time for a shake
test.  I went to the garden and dug down about six inches below and between
the raised beds.  There was a mixture of deep red clay and subsoil.  We soaked
the soil (at dusk while swatting a million mosquitos) to loosen it up and
added about 50% sand from the kid's sandbox.  I took a big handful of straw
from the mulch pit, cutting it into six inch lengths while Patrick stirred the
bucket.  I sprinkled the straw in while Patrick kept stirring.  We took a one-
half gallon paper milk carton with the top compressed and one side cut off.
We filled the milk carton by hand, slightly compressing it by fingers (and to
also remove excess water -- it was dark by then).

We had been running a dehumidifier in the basement after water overloaded the
rain gutters during a recent gully washer (it would have handled it fine, but
the soil was back filled by a profit minded contractor too soon, causing a
font "T" overhang to sag a bit).  Sitting the brick in front of the
dehumidifier was the closest thing we had to sunshine for a few days.  You can
tell the original soil sample was very high clay as the brick had quite a few
cracks.  The brick dried to a very hard brown color with the straw sticking
out in places.  Adding 50% again as much sand may have produced less cracks
(there was no crumbling).  You could tell where we where impatient and didn't
work some of the clumps together as much as we should have in places as this
was where the bigger cracks were too.  It was a good experience and we'll have
to make a wheel barrow full of test bricks this summer in anticipation of the
oven and tool shed projects.

Dave