Building with the earth itself is another sustainable approach
to architecture. Adobe, cob, and rammed earth all utilize a mixture
of sand and clay, which can be found locally. Earthbag building
is a novel way of stacking polypropylene bags filled with earthen
materials to make walls or domed structures. The bags can be
filled with earth from the building site to create thermal mass
that helps buffer temperature extremes, or they can be filled
with crushed volcanic rock that serves as insulation.
Cordwood walls utilize short sections of tree branches or trunks
in a mortared matrix. This technique provides a nicely textured
wall that is both insulating and has thermal mass. With all
of the draught and beetle killed trees in the Southwest, cordwood
is readily available. The amazingly beautiful "pudding stones" that
are common in our area are another resource that can find their
way into our buildings.
There are some unusual manufactured materials (continued on page
45)


