Hempcrete is a truly environmentally sustainable method of building, from production of the raw material throughout the lifespan of the building. Hemp combined with lime offers unique and outstanding natural properties that cannot be matched by conventional building materials.
In comparison with conventional building materials, the processing of industrial hemp involves very little embodied energy. There is no heating, treating or modifying involved. The raw material is simply chopped into pieces small enough to be mixed in a pan mixer with aerated lime and water.
Hempcrete displays extraordinary thermal performance. It has the ability to both insulate and store heat, providing occupants with a more comfortable and constant internal temperature. Combined with a lime or clay plaster finish to internal surfaces, hemp-lime provides a passive means of regulating relative humidity, reducing reliance on mechanical heating, cooling and ventilation.
Residential construction is responsible for producing 23.8 megatonnes of carbon dioxide (CO2) annually. The manufacturing of synthetic insulation materials contributes enormously to their high embodied energy and the overall CO2 equation.
Hempcrete buildings act as a carbon sink, preventing the release of CO2 back into the atmosphere. An average size house constructed of hempcrete will remove about 20 tonnes of CO2 from the atmosphere over its lifetime.
This makes hempcrete construction a negative carbon emitter because of its ability to lock up more CO2 in the building than is emitted during its production, processing and transportation.
Lime is the wonder ingredient often overlooked. Lime absorbs CO2 during its carbonation process which helps to reduce the CO2 in the air. It’s a highly breathable material with natural anti-bacterial and insect-repellent properties, and is considered carbon neutral.
While CO2 is emitted during its manufacture, the CO2 is reabsorbed during its drying process and continues to be absorbed indefinitely. From production to finished building project, lime is considerably greener than Portland cement.
On a one-on-one material basis, hempcrete is comparable to other building systems such as brick veneer. In regard to hempcrete, the fixed costs are the materials (hemp hurd, lime binder). The variable cost is in the labour. This is where the DIY owner-builder can achieve financial savings—the building team can comprise family and friends.
Copyright © 2020 HawaiiHemp.earth - All Rights Reserved.