Re: GBlist: re: can we build without cutting trees

[Speireag Alden <Joshua.M.Alden.91@alum.dartmouth.org>]

Sgrìobh Yaya Balinci:

>Please, for your sake, and in light of questionable materials and 
>appropriate technologies, Look into adobe, cobb and/or straw-bale 
>before you make your decisions. Contrary to popular unbelief you can 
>build these structures in any climate provided you have a good roof. 
>A wooden house can rot if not built properly. So can clay and straw. 
>But if built properly nothing will look as beautiful and feel as 
>satisfying.

     Although I agree that he should look at these methods for France, 
I beg to differ with the statement that they are appropriate for "any 
climate".

     Adobe and cob have many fine characteristics.  One of these is 
mass.  Their insulative value is not much better than stone, but they 
have a lot of mass.  That's what makes them so comfortable in many 
moderate climates; they moderate temperature swings.  Also, radiant 
mass is a subjectively very comfortable way to stay warm.

     However, if you build a house out of adobe or cob in Minnesota, 
you're going to be very cold in the winter unless you use a *lot* of 
fuel to heat, and even then the exterior walls will always radiate 
cold.  We discussed this a year or so back, and one fellow reported 
growing up in a stone house in north-central United States, and they 
were cold all year round, even with fires blazing.

     So, mass is both a virtue and a flaw, and the wise builder knows 
how to use it to advantage rather than disadvantage.

     The problem in any climate which is too cold or too hot for long 
stretches of time is that the mass eventually also attains that 
uncomfortable temperature, and then trying to get it back to comfort 
can take a lot of energy.

     Now, if you build a massive wall and then insulate it effectively 
on the outside, you'll have a structure which performs very well as 
long as it's continuously occupied.  So a bit of insulation can 
greatly extend the useful geographical range of adobe and cob.

     Straw bale, on the other hand, is insulation, with a thin layer 
of mass on either side (the stucco).  So it can do very well indeed 
in cold or hot climates.  Of course, just as you do with any building 
method, you still need to get the details right.

-Speireag.
-- 
Speireag Alden, aka Joshua Macdonald Alden
Usually found somewhere in the wilds of New Hampshire.
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