The Top 8 Benefits of Hempcrete

The hempcrete building material is comprised of the woody core of the industrial hemp plant, also known as herd or shiv, and lime-based binders. The lime portion of the mix acts as a biocide, which makes hempcrete buildings naturally pest and mould resistant.

1. Good Thermal Qualities

Hempcrete buildings have excellent insulation properties (up to R4.2) when built to a the recommended 250mm thickness. Buildings stay warm in cold weather and cool in warm weather without a constant input of energy. With good insulation, considerable amounts of money and energy can be saved.

2. Reduces Air Leakage and Draft

The monolithic construction method used in hempcrete buildings drastically reduces air leakage and draft. This is achieved through a continuous insulation from the wall to the ceiling.

3. Breathability

The hempcrete structure allows transfer of moisture through walls and avoids condensation build-up. This means that the humidity and air quality inside the building are controlled.

4. Good acoustic qualities

Hempcrete walls have great acoustic absorption. A rendered hempcrete wall will reflect most of the sound ~900Vson m/s (speed of sound per m/s) Compared with steel which is ~6100Vson m/s. WAny remaining sound traveling through the wall will be absorbed by the porous constitution of the hemp wood and the hempcrete itself.

5. Removes Carbon From The Atmosphere

During the growing cycle, hemp sequesters large amounts of CO2. 1m3 of hempcrete locks in 150kg of CO2 i.e. approximately 5.4tons of CO2 per house. Although the manufacture of the lime binder (including harvesting and transport) does release CO2 into the atmosphere, the result is that hempcrete removes more CO2 out of the atmosphere than it contributes, making it a carbon-negative material. This is a great thing for the earth…every little bit counts!

6. Fire Resistance

The lime in the binder makes hempcrete fire resistant. Hempcrete is non-combustable and has a fire rating (FLR) of 60/60/60. We are currently testing hempcrete walls to achieve 120/120/120.

7. Pest, mould and mildew resistance

The lime portion of the mix acts as a biocide making hempcrete buildings naturally pest, mould and mildew resistant. In addition, hempcrete buildings provide an optimum humidity range in which mould and fungi do not grow.

8. Free of Toxins

Many building products and their manufacturing processes use and release large amounts of polluting components. These include V.O.C's (volatile organic compounds) which are in glues, paints, polyurethanes etc. The mix of hemp wood and lime creates a long lasting, toxin- free building product that can offer zero carbon constructions. This makes hempcrete allergen free.

ORIGINAL ARTICLE BY HEMPCRETE AUSTRALIA