Cob: Oklahoma thoughts and concerns

[bobodod at cox.net]

Hello all. I haven't been keeping up with the list real well, so forgive me
if any of these ideas have already been raised.

    A friend brought up the concern that the extreme temperature and weather
variations - strong winds and intense storms - we experience in Oklahoma
would wreak havoc on a Cob building. He wondered if a change of 40 degrees
Fahrenheit wouldn't crack the walls. Or just the very hot Summers and cold
Winters might do the same. Any opinions on this? By the way, the climate
here is slightly above average humidity, I think.

    Another friend brought up another concern involving the heat here. In
the Summers, the temperature often doesn't get below the high eighties,
unlike the desert where the temp will drop several dozen degrees at night.
He thought that with all of the thermal mass of a Cob building, the walls
would not be able to shed the heat of the day at night. By the end of Spring
and beginning of Summer, this could mean living in a sauna.

    One idea yet another friend ; ) came up with in retaliation to all that
heat was to do some sort of radiant cooling in the walls. He said he got the
idea from "This Old House" or something similar. He was flipping the
channels on his TV and heard "Oklahoma" mentioned. He stopped to check it
out and it turned out that some home builder here in this landlocked State
had buried a coil of pipe (not sure what kind), deep in the ground - at
least six feet - several feet away from the house. He then ran pipe from
that coil to pipe which he imbedded in the walls of the house he was
building. My friend wasn't sure if the guy'd filled the pipe with water or
what, but the idea was to let the Earth cool the liquid in the pipes
overnight, then pump that liquid into the wall pipe in the morning,
completing the cycle the next morning.
    Has anyone heard of this? Any thoughts as to doing the pumping action
with a modified bicycle if someone were wanting to be free of the daily
electricity needs of the pump? Or would the physics of that be impossible
(meaning a couple hundred gallons or whatever being pushed around by two
scrawny human legs)? Would Cob dry and settle correctly with pipe buried in
it? I've heard that the Earth from about 6 feet and on down, stays at a
constant temp of 72 degrees Fahrenheit. Can anyone confirm this? And if
that's the case, I imagine that it'd be advantageous, if not bothersome, to
pump the liquid every single day as it'd help to regulate the indoor
temperature year round. And round about, tackling the first concern I
mentioned of the walls being able to take temperature extremes.

I'm going to give my fingers a rest now.

Sean Fenton
Oklahoma City, OK