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Re: passive solar greenhouse/strawbale
At 07:46 PM 11/11/97 -0600, Bruce Brummitt wrote:
>Out of curiosity...where do people on this list walk on this permaculture
>I'd like to hear what other folks build their buildings from, how they heat
>and light them, what they eat, etc...
>Learning, always learning,
>Bruce Brummitt and Cheryl Valois
>"With Liberty and Justice...for All"
It's the old rat infestation and bug hotel conversation again. Reminds me
of when I first started building earth sheltered houses when everyone talked
about how damp, fungi filled, and dark it would be, which would be true if
we left out ventilation and windows.
There are many structures of straw in Europe that have been in existence for
over a hundred years and are not any more prone to collapse from mice mining
than are stick frame, or adobe structures. It's all in the care and skill
of the builder. With thoughtful and careful design straw bale is a
wonderful material that will outlast the builder. There are structures
standing in Nebraska continuously occupied for over 80 years. And as far as
I know they have mice and fires and bugs in Nebraska so someone did
My concern about any material is if by taking it for one purpose we are
impoverishing the environment. So is straw more important as a carbon and
biomass source for the soil where the grain is grown or is it more important
as a building material thus saving forests. I think that this is a serious
question and I am slowly reaching the conclusion that sustainable forestry
would be more ecologically sound than straw harvesting for construction.
Unfortunately sustainable forestry is not how most timber is produced.
Certainly I would rather see straw bales in a wall than going up in smoke
where most of the worlds' straw is presently going. It seems that in my
area of the southwest the best material is adobe or rammed earth,
particularly if you set aside the topsoil and makes bricks out of subsoil.
The problem with this is how do you insulate for cold winters. I have not
seen a truly elegant solution to this problem, primarily because it either
requires building two walls with a hollow core for cellulose fiber, or
straw, etc. or using styrene/urethane exterior insulation. One solution
doubles up your labor and materials to a profligate level and the other
contributes to the petro-chemical pollution madness.
So my wife and I are in the process of building with straw bale exterior
walls on the north, east and west with adobe interior walls for solar mass.
We am incorporating a Russian stove, or kacheloffen for backup heating
because we can coppice the existing trees on our place for fuel. Solar heat
comes from south facing windows and an interior greenhouse. The house is U
shaped with the greenhouse in the opening of the U. We are using the Watson
wick system of waste disposal which means all our grey and black water is
held in a gravel or pumice basin under the greenhouse from which we hope to
grow tropical and semi tropical plants in addition to the occasional tomato
and pepper. There will also be some Btu benefit from water temperature and
some storage benefit also from the water soaked basin.
We looked at many options before making this decision and even though we
couldn't reach that 100% purity level we feel that we have made the best
decision for the environment in which we live. A big problem is the
regulatory agencies which one has to deal with who are intent on making
construction of a home part of the great industrial process. The Universal
Building Code, to my mind is an oxymoron - how can it be universal? We are
forced to build foundations to counter frost heave which doesn't happen here
in Santa Fe, NM. Maybe it makes sense in Minnesota but there are structures
here, including the oldest house in the USA which are build on field stones
laid at near grade and they haven't moved in over two hundred years. Tom
Watson, (see Watson wick above) is anxious to challenge the regulators and
the national building codes with a civil suit claiming the right to housing
a civil right and that regulation and codes make it impossible for those
with little or no money to have housing. I have to agree with him. Most
construction is over engineered and eliminates the possibility of
innovation. At one time in the recent past Texas had no regulations on
dwellings unless they were built with commercial use in mind. If you wanted
to build a house out of refrigerator cartons it was your house and you had
to live in it and if it didn't endanger you neighbors it was ok. That seems
sensible to me.
On materials I think that Pliny Fisk III of Center for Maximum Building
Potential has the best criteria. His system is based on a data base of your
biome which lists all of the resources and from this data base you are able
to put together the best possible materials for you environment. It may be
bamboo if you are southern coastal, or adobe if you are desert southwest.
Mainly it is a system of careful observation of the region and then good
design based on the cleanest ethics you can evolve.
I agree with Gene Monaco on vapor barrier that is I am not using them. I
much prefer breathing walls which transpire over the annual cycle. If you
design your shower to spray on the walls then you will have a problem - but
that isn't inherent in the materials but in poor design. I prefer a shower
in the greenhouse where the humidity serves multiple function. Problem with
exterior vapor barrier is that any moisture is trapped exactly where you
don't want it in the strawbale or in your insulation if you are building
P.S. I built first straw bale construction in Belarus (53 latitude, 29"
rainfall, 90-97% relative humidity) two years ago. Construction is used as
livestock barn, and of course doesn't have any heating system. So far it
hasn't created any problems, including mice invasion in walls. It holds very
nice temperature in winter (last year - minus 30 F) even with no insulation
on the roof and simple one glass windows. Seems to work fine even in such a
Scott & Arina Pittman
PO Box 3702
Pojoaque, NM 87501
Ingenio Patet Campus