Can hemp be a game changer in the home construction industry and become a more valuable crop in the Upper Midwest? That is what a new study in the city of Fargo, N.D. is trying to determine.
The Agricultural Utilization Research Institute (AURI) partnered with a construction company and a hempcrete manufacturer on a side-by-side comparison demonstration project to determine how hempcrete, a bio-composite material used for insulation, performs against traditional fiberglass insulation.
A number of environmentalists, farmers and builders have anecdotally touted the benefits of hempcrete such as it is – energy efficient and reduces mold in homes and buildings, while improving indoor air quality, based on the belief of the hemp plants’ absorption of carbon in the air.
However, there is scant data or research available to support these benefits, so researchers on this project will work to fill in some of those details to create a bigger market for hempcrete in the green building sector.
To obtain this important data, Fargo, N.D.-based Grassroots Development built two identical homes with dimensions of 13 feet by 23 feet with 12-foot ceilings. Both have a traditional wood frame, however the walls of one home are filled with fiberglass insulation, while the walls of the second home are filled with hempcrete, which contains the hurd of the hemp plant mixed with a lime binder and water. Homeland Hempcrete in Bismarck, N.D. supplied the hempcrete.
Riley Gordon, Principal Engineer with AURI, installed sensors in both homes to monitor moisture, air temperature and energy usage. The readings will be collected and analyzed by the Center for Energy and Environment (CEE) over a 12-month period to provide a complete picture of how hempcrete compares to traditional fiberglass over the course of a cold winter and hot summer in North Dakota. Researchers at CEE will also perform a blower test to provide additional numbers on air leakage performance, ambient temperature and humidity levels in the two homes.
“There is a lot being said right now about what hempcrete can do, but there just isn’t a lot of good research to back up any of the claims with numbers,” Gordon said. “This study will finally be able to answer some of those questions. If we get some good data, it will help inform not only the construction industry, but growers and processors too. There are a lot of groups who have been holding out on making decisions about investing so hopefully these results can help de-risk the opportunity and drive decisions.”
Working with hempcrete is a labor-intensive process. The material’s ingredients are blended in a large concrete mixer, after which workers pack the material into the frame of a building by hand while it is still wet. However, this allows for a more precise installation process than traditional fiberglass as workers are able to fill the hempcrete into the nooks and crannies of a structure.
AURI’s Business and Industry Development Director Harold Stanislawski made the connection with Homeland Hempcrete and Grassroots Development. The companies wanted to conduct a research study, but ran into cost feasibility issues. Gordon stepped in with a solution to kickstart the partnership.
The collaborators received a quote of roughly $25,000 for hempcrete installation, monitoring equipment and analysis of data. That initial figure was too expensive, but to keep the momentum going, Gordon agreed to install the air, energy and moisture monitors in the two homes.
“The travel time for a third party entity and installation were a big cost for the project,” said Gordon. “I was able to install the devices with some technical direction over the phone. That is one of the benefits AURI can bring to projects like this. We know a lot of people involved in the hempcrete industry and we can serve as a connector to bring different groups together. We also have the technical expertise to guide the monitoring and data collection.”
Sydney Glup, Sustainability and Design Coordinator at Grassroots Development, said the company has been wanting to put together a study like this for some time. “The partnership that developed among several different stakeholders is ultimately what provided the boost to get the idea off the ground. The goal is to bring awareness of the many benefits of using hemp in construction materials to a larger market,” Glup said.
Hempcrete has the potential to be transformative for the region’s agriculture and construction sectors while also bringing potential benefits around energy and indoor air quality, which underscores the importance of these studies to spur investment in processing advancements and encourage more farmers to grow the crop.
In the field, hemp is a high performing rotational crop that is effective at soil remediation and carbon sequestration. Hemp farmers stand to benefit from increased demand for the crop due to the growth in the popularity of hempcrete. Market growth for hemp would also encourage more farmers to plant hemp.
“We hope that with this data we can break through some of the limitations that are keeping hempcrete in that niche market category,” Glup said. “I really believe there is a shift right now from building homes as fast and as cheap as possible to focusing on building homes that address health and wellness and the environment. Plus, with all the supply chain challenges right now we can keep the materials closer to home and hopefully continue to reduce the price of construction using novel products.”
Today, building with hempcrete is about 20 percent more expensive than traditional building materials. But Glup is quick to point out that the cost is recouped by cost-savings over the lifespan of a building. Some estimates say hempcrete can save 40 percent on energy costs annually. Plus, with more acres planted and additional investment in processing technology, the price of hemp-based construction products could become more competitive.
“We are very grateful for AURI’s support on this project. It has been a dream of ours for some time to be able to gather this kind of data, Glup said. “[Hempcrete] is a grow-your-own type of building material with a lot of social and environmental aspects to it. We feel strongly about the benefits of hemp, and we are so happy to be able to have the support of partners to be able to see this product grow.”
