Jun
This is one of the newest alternative building material in the green building world. It is basically re-pulped paper fiber mixed with a little concrete and sand. Occasionally clay is used instead of concrete; this is called paper adobe or padobe. The overall cost of papercrete houses can easily be less than a dollar a square foot.
The paper used for papercrete can come from anywhere, even those slick magazines. In fact, those are perhaps more desirable because they have clay in them. Once the paper is collected it is sometimes soaked in water before being placed into a large mixer with the concrete or clay and sand. It is then shaped into blocks, like adobe, or poured into slip forms, like rammed earth. Occasionally the earthbag technique is used too. It can also be used as a plaster for other alternatively built houses. This is perhaps, the better way to use it.
Papercrete has several problems to work out. It is such a new concept that it hasn’t been tried long term (over twenty years) yet. It is extremely susceptible to moisture because it essentially acts as a sponge unless it is plastered or coated. Even then, if moisture gets past the plaster, it creates an ideal habitat for mold. Some early papercrete houses are already uninhabitable because of mold problems. Papercrete houses also pull moisture from the ground if it is in direct contact with the earth. Again, not a good idea.
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