What Is Hempcrete and How to Use Hempcrete for Roofs


Roofing / Wednesday, June 12th, 2019

Hempcrete is a building material made of hemp hurds and limestone. Hempcrete is bio-composite and offers many benefits that other building materials lack. It is fire resistant and offers great insulation from the outside temperature. Hempcrete has been used in buildings in Europe decades ago, and the buildings still stand in perfect condition. Hempcrete is a great material to be used in roofs. If you are considering hempcrete for roofs, read the following commonly asked questions.

What Is Hempcrete and How to Use Hempcrete for Roofs

  1. How can I use hempcrete for roofs?

Hempcrete for roofs requires a one-inch breathable space between the top side of the hempcrete and the underside of sheeting material. This material can by plywood or hemp board.

  1. Do I need special permission from the building department to use hempcrete in the roofs?

United States Constitution allows people to build their own shelter and you can use non-conventional or alternate building material codes for the approval of using hempcrete in your building.

  1. Can hempcrete roofs withstand rain?

Hempcrete is a very durable material and it can withstand rain, even without any plaster or stucco finish.

  1. Does hempcrete require expansion joints?

Hempcrete does not require expansion joints.

  1. What is the density of hempcrete?

The density of hempcrete varies between 94 and 135 Kg per meter cube.

  1. How long does it take for the hempcrete to cure before rendering with lime?

Depending on the climate, it usually takes 6-8 weeks. Hempcrete should be with 10-15 percent moisture.

  1. Can I use hemp for retrofitting existing building?

Yes, it can be done by removing the drywall and exterior cladding.

  1. What are the benefits of using hempcrete?

Hempcrete is an environment-friendly material. Furthermore, it provides exceptional insulation resulting in less energy costs, and it is extremely fire resistant.

  1. Is hempcrete costly?

Hempcrete cost is equal to the traditional cement buildings.