Cutting Edge Green Building, Hempcrete Masonry Just Got Better

by | Dec 12, 2019

Written by Jessica McKeil

Jessica McKeil is a cannabis writer and B2B content marketer living in British Columbia, Canada. Her focus on cannabis tech, scientific breakthroughs, and extraction has led to bylines with Cannabis & Tech Today, Terpenes and Testing, Analytical Cannabis, and Grow Mag among others. She is the owner and lead-writer of Sea to Sky Content, which provides content and strategy to the industry’s biggest brands.

Hempcrete, a building material created by combining the robust fibrous core from hemp with lime and water, is experiencing a bit of a heyday. It's eco-friendly, relatively affordable, and it has many thermal benefits for interior and exterior applications. It’s one of the most sustainable building materials available today.

With the launch of their new Just BioFiber Block, they have created an eco-friendly building medium that can finally compete with conventional building materials.

The Benefits of Hempcrete as Building Material

Hemp as a building material is nothing new, but with so much focus these days on the plant for cannabidiol (CBD) extraction, its industrial applications are often forgotten. However, with the global economy throwing everything into hemp cultivation, presumably, there will be a growing supply of hemp fibers as well. The stalks, fibers, and other less-valuable parts of the hemp plant are far from waste products. As many innovative companies are proving, there is significant value in hemp beyond its applications for CBD.

Before the development of the JustBioFiber building bricks, hempcrete was sold as an eco-friendly building material. Although not appropriate for load-bearing applications, companies such as IsoHemp in Fernelmont, Belgium, advertise their hemp-based blocks for interior and exterior wall insulation as well as a lightweight and efficient solution for floor and ceiling insulation.

For acoustic insulation, there are few building materials with better ratings. Compared to cork, wool, and application-specific, sound-absorbing foam, hemp has a better acoustic absorption coefficient rating. As an added benefit, hempcrete insulating bricks are typically incorporated within a structure and therefore have a better design aesthetic than exterior-mounted, sound-absorbing foam.

Finally, hempcrete is naturally fire-resistant without the addition of fire retardants or toxic chemicals. According to the ratings provided through most hempcrete companies, hempcrete as a building material falls under a Class B rating. This rating means over two hours of fire resistance (dependant on the specific brand, coating, and size).

While nobody is arguing against hempcrete's insulation properties, nor its capacity to replace certain materials as a green solution, hempcrete has struggled to move into the commercial building market. As a non-load bearing material, it struggled to hold its own against more conventional building materials like stick-frame, concrete, and ICFs.

Improving on Hempcrete, Giving Hempcrete a Competitive Advantage

Until JustBioFiber's design, hempcrete was only suitable for non-load bearing building applications. Strategically useful, but only to an extent. With innovative changes to the shape and production process, the Just BioFiber Block provides structural integrity on top of the acoustic and thermally insulating qualities.

According to Just BioFiber, each block weighs roughly 28.7 lbs (13 kg), and the hemp-fiber makeup makes them both air-permeable and non-toxic. The unique interlocking system allows for speedy construction, saving on traditional labor costs. As per the product specifications, labor costs are $32/sqft (1 m2) per working hour.

The new design still maintains all the fire-resistant and thermal qualities of conventional hempcrete blocks. The Just BioFiber Blocks have a two-hour or more fire-resistance rating, with no smoke or flame spread during testing. Acoustically they maintain an Acoustic Absorption Coefficient of between 0.10 to 0.55 NRC, although this may vary depending on the coating.

The interlocking blocks make for rapid construction, again, just like Lego. They are also suitable for multi-story dwellings. On-site, the blocks are easily cut using standard tools and fastened in place using stainless steel parts (to extend lifespan). Although this is a relatively new material, Just BioFiber predicts a 100-year lifespan.

Putting Hempcrete to the Test

Just BioFiber made a few headlines in the construction world this year as it completed its first project using the Just BioFiber Blocks. The Harmless Home, built on Vancouver Island in Canada, is the first structure built using the hempcrete innovation. The vision behind this project was to create a net-zero residential housing project. It is the brainchild of Anderson Greenplan with Ridgeco Developments in charge of the construction. A report by Global News stated, “It's being hailed as the most sustainable, safest and most energy-efficient house possible.”

In building applications, hempcrete is being hailed for its fire resistance, mold resistance, and durability. But what is earning the most attention for Just BioFiber is the carbon-capturing qualities of its products. The manufacturing process captures and retains atmospheric carbon dioxide within the hempcrete blocks, using all-natural and rapid-renewable materials: hemp fibers. In an upcoming five-story, 112,000 sq ft (10,405 m2) facility, Just BioFiber predicts an ability to capture 715,000 lbs permanently (324,600 kg) of carbon dioxide.

This second pilot project, proposed for Kelowna, British Columbia, is a design that combines an indoor storage site with office space and will adhere to the CaGBC's Zero Carbon Building Standard. The EcoLock Self-Storage, Wine Storage, and Co-Work facility is currently still in the proposal stage.

Other projects are also on schedule, including a zero-emissions fire hall, an elementary school, and several commercial properties.

A Product with the Potential to Revolutionize Building Practices

As Terry Radford, Just BioFiber CEO, explained to CBC News, “We're about the same as insulated concrete form, but we're much faster. We're about half of the build time of insulated concrete form because there's no steel, no rebar, and no concrete, so you don't have to wait for that to set up.”

Just BioFiber builder, Mark Faber, is convinced it's time to make the switch. He told Global News, “So far, we've seen that it is easy to use and put together — once we develop and really dial in the system, I think we'll be able to be competitive with all other building systems out there.”

Conventional building materials are notoriously toxic, with substantial environmental impacts thanks to the manufacturing process, waste materials, or emissions. Hempcrete offers an eco-friendly alternative, and thanks to the redesign by Just Biofiber, it could finally give these conventional materials a run for their money.