Benefits of Hemp as a Building Material: Interview with Steve Allin

In our July/August issue of Cannabis Science and Technology, the feature article From the Ground Up: The Sustainability of Hemp from Seed to Solution by Associate Editor Erin McEvoy explores hemp's potential to be a sustainable resource for textiles and building materials, plus the challenges to its widespread adoption. The article includes insights from Lawrence Serbin, founder of Hemp Traders and Steve Allin, founding director of the International Hemp Building Association.

In this interview, Allin shares more details on the versatility and benefits of hemp as a crop and as a material used in construction.

Dive into the interactive July/August 2025 issue to read the full feature article and learn more about potency determination, limit of detection determination, packaging and cannabis preservation, and decontamination!

Transcription

Erin McEvoy: Today we’re joined by Steve Allin, director of the International Hemp Building Association to discuss the sustainability of hemp as a building material. Thank you so much for joining us, Steve.

Steve Allin: Thank you forjoining me. It’s a pleasure.

McEvoy: Could you walk us through the life cycle of hemp-based construction material from cultivation to use in construction projects, and what is one example of a noteworthy construction project involving hemp?

Allin: Primarily it's a crop that has multiple uses, and is a sort of crop that can be used to improve the soil and adds to a more sustainable, or even organic system of agriculture by providing a rotation crop to lower the use of herbicides and to maintain some of the mineral balance in the soil, because it does return quite a bit of its uptake in leaf matter and waste left behind in the crop. So it's very good for tillage farming and for the health of the soil. So that is one benefit.

The other benefit is, then, that it just so happens that the nature of the materials that we use primarily the fact that they're water vapor porous. So both the fibers and the cellulose chips of lightweight wood that come from the center of the stem, both have a very porous ability. So they handle moisture. Let's put it that way. They have benefits with moisture when it comes to textiles, and it has all sorts of advantages in the structure of this lightweight cellulose wood, in the way that it behaves, both structurally and insulation wise and vapor control wise. So this means that we have this material that is really good, has benefits to produce, that when you use in a particular way, which is fairly simple type of processing, doesn't involve loads of chemicals or anything, we can produce a material that provides an envelope to a structure, whether it's existing or a new one, right? So you're insulating or encasing or building with material that has these abilities to provide great levels of comfort while working at very low energy consumption rate. And they’re nontoxic, and they're nonflammable. So those advantages aa\re quite simple to identify.

When it comes to, you know, major projects that have now been many all over the world, that have been quite a large scale, there are projects that range from temporary type shelters for shacks for untouchable women in the south of Nepal to luxury homes on the west coast of Canada, or all sorts of industrial buildings, office buildings clad with hempcrete, social buildings, government buildings, and also big industrial buildings, where they're used for storage, again, lowering energy consumption. So those kinds of projects are now available for people to find out about. I wrote a book called “Hemp Buildings: 50 International Case Studies,” which highlights 50 completely different types of projects using every different type of use of hempcrete. So that's probably a place to go.