Hemp is perhaps best known for its
Omega-3 and -6 fatty acids that make it a great addition to a
healthy diet, and as a cotton substitute in ecologically-sound
clothing and bedding. But it is also a versatile,
environmentally-sound building material.
A hemp crop can be
grown without the use of herbicides or insecticides and produces up
to four tonnes of material per acre per year. Hemp is categorized as
a bast fiber crop. It has a stem consisting of an outer skin
containing long, strong fibers and a hollow wood-like core or pith.
Processing the stems results in two materials: hurds and fibers,
both of which have properties that make them extremely useful in
building construction.
A variety of
wood-like products, such as fiberboard, roofing tiles, wallboard,
paneling, insulation and bricks, can be made from the compressed
hurds. The fibers can also be used like straw in bale wall
construction or with mud in a sort of modified cob style of
building.
Foundations can be
made out of hemp hurds. A hemp plywood frame is filled with a hemp
hurds combined with lime, sand, plaster, some cement and enough
water to dampen, and then let to set for a day and to harden for a
week. A sixth century hemp-reinforced bridge in France is testimony
to the stone-like strength and durability of this material, which
has come to be known as “hempcrete”.
Hemp building
boosters claim that hempcrete foundation walls are up to seven times
stronger than ...
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Rolf Priesnitz is the Publisher of Natural
Life Magazine. He also has 40 years experience in the
construction industry. Read his complete
bio.
