THE INGREDIENTS

How is Hempcrete Made? What is the process?

It takes only three (3) materials to create hempcrete: which is (1) hemp hurds (or “shives”), (2) lime binder, and (3) water.

Hemp hurds are the woody inner parts of the hemp stalk. They are first broken into fragments and separated from the fiber by way of breaking and scutching separating impurities from raw materials by using a machine called scutcher.

The lime which is used in the mixture acts as a binder. Hemp hurd contains a high silica content that helps it to bind well with lime.

THE PROCESS

Hemp, Lime & Water Scientific Process

Hempcrete has a λ value (conductivity which the rate of the passage of heat through the material) of ~0.076 – 0.11 W/(m.K) when mixed with a mild to moderate hydraulic lime consisting of ~85% hydrated lime and ~15% clay or pozzolans.

For Floor Slabs, a more hydraulic lime is used and sand is added to improve strength and water resistance λ value ~ 0.13 W/(m.K).

For the Ceiling Insulation and the internally insulating stone wall coating, a pure hydrated lime is used and a higher percentage of hemp to provide a more insulating and lighter mixture λ ~0.08 W/(m.K)

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