Hempcrete is a bio-composite made of the inner woody core of

the hemp plant mixed with a lime-based binder. The hemp core or “Shiv” has a high silica content which allows it to bind well with lime. This property is unique to hemp among all natural fibers. The result is a lightweight cementitious insulating material weighing about a seventh or an eighth of the weight of concrete. Fully cured hempcrete blocks float in a bucket of water. It is

not used as a structural element, only as insulating infill between

the frame members though it does tend to reduce racking. All loads

are carried by internal framing. Wood stud framing is most

common making it suitable for low-rise construction. Hempcrete buildings ten stories high have been built in Europe.

Hemp can be made into any building material, including fiberboard, roofing, flooring, wallboard, caulking, cement, paint, paneling, particleboard, plaster, plywood, reinforced concrete, insulation, insulation panels, spray-on insulation, concrete pipes, bricks, and biodegradable plastic composites which are tougher than steel.

Foundations can be made out of hemp hurds, a processed based on ancient technology adapted for modern use. To do this, set up a plywood frame (preferably hemp plywood), then fill with a mixture of hemp hurd (wood chip-like substance) and combine with lime, sand, plaster, some cement, and enough water to dampen, and let the mixture set for a day. Then take the frame down, but let the mixture continue to harden for about a week. The lime and the hurds create a chemical reaction which binds the mixture together. Amazingly these structures continue to get harder and stronger everyday until they fossilize, as is testament by a 6th century hemp-reinforced bridge in France. After this happens, the hemp foundation walls are as strong as stone.

Hemp foundation walls are 7 times stronger than concrete foundations, half as light, and three times as elastic, which means that these building will bend, but not break. Because of their superior strength and flexibility, hemp foundations are resistant to stress-induced cracking and breaking. Even earthquakes and other natural disaster cannot break or crack these structures.

Hemp foundation homes and buildings are self-insulated, including thermal and sound insulation, resistant to rotting, rodents, insects, and they are fire proof, waterproof, weather resistant, and the walls breath so the rooms do not get stuffy. Hemp homes stay warm in the winter, and cool in the summer.

If hemp were legal in the United States, it would be the cheapest source of raw material for concrete-like foundations. Plus hemp hurds can be processed in existing wood mills without major changes to the equipment. Hemp-foundation homes are ecologically appropriate because they are inexpensive, and can be prepared on site using only a cement mixer, and the material would be cheap and abundant.

Foundation floors can be made in much the same way as the foundation. Hemp resists seepage, and so hemp cement is applicable for pouring onto a soil base to make a foundation floor. The floor insulation hardens into a solid mass which will not shift under pressure.

A German company produces a product called Mehabit, a hemp hurd substance covered with coal-based bitumen, which is sticky, and when leveled out on a hemp cement floor, will dry to form a thermally and phonetically insulated floor.

Washington State University has produced hemp fiberboard is lighter, twice as strong, and three times as elastic as wood fiberboard, plus it has sound proofing and pressure isolative characteristics absent from wood fiberboard. These composites are also resistant to pests, moisture, and funguses.

The process involves chipping the hemp stalk, bonding it together with resins and glues, and clamping it down into molds under high pressure until it hardens.

Concrete pipes can be made out of hemp fiber which cost 1/3 that of polypropylene. These pipes have greater flexibility, greater elasticity, and are resistant to cracking.

Stones can also be made out of hemp by wetting the stalk’s cellulose, and forming it into a hard black rock, which can be cut, drilled, cast, carved, or formed into any shape.

Hemp building material could allow us to replace the need for wood, bricks, and fiberglass insulation.

Germany and France are using hemp for construction material, replacing drywall and plywood. A French company has built over 250 homes using hemp materials. Hemp homes have also been built on the Pine Ridge Reservation in South Dakota. Using hemp is economically smart and ecologically appropriate, plus the homes built with hemp are as hard as stone and are not subject to natural disaster. Wow, sounds kind of like a miracle, doesn’t it? What are we waiting for?*