Putting hemp housing to the test.
We’ve heard a lot about how hemp is a rising star when it comes to materials for housing — cost effective, energy efficient, carbon negative and biodegradable.
But how does it measure up compared to the status quo in construction? A North Dakota organization aims to find out.
Grassroots Development is behind two small houses being built in Fargo. The homes are identical in design, reports Minnesota Public Radio: 13 by 23, with 12 foot ceilings and a loft in each. They both have wooden frames — but one will have fiberglass insulation and the other a layer of hempcrete to insulate the walls.
Hempcrete is a composite of the inner woody core of the hemp plant and lime binder, according to Grassroots Development. It has low thermal conductivity, making it a solid candidate for home insulation. It’s also resistant to moisture and therefore mold, as well as fire.
Grassroots Development wants to see how the two homes compare over time. They’ve installed sensors in the walls of both houses to monitor moisture and air temperature, and will also track energy consumption. The Minneapolis-based Center for Energy and Environment is on board to help analyze data from each home, according to MPR.
"We're just trying to get that concrete, non-biased research to contribute to the industry so we can troubleshoot and figure out how to do better,” Sydney Glup, sustainability consultant at Grassroots Development, told MPR. “We want it to be so that anybody who wants a healthier dwelling can afford it.”
It’s the first study of its kind, according to Riley Gordon, an engineer with Agricultural Utilization Research Institute, which helps develop new markets for Minnesota crops.
"Up till now, a lot of the talk has just been a lot of claims that haven't really been backed up by a whole lot of data,” Gordon told MPR. “So I think this is going to, for good or for worse, provide some answers to questions that I've heard pretty often about this material. So I think it's a very important study, and timely."
One thing is clear already: It costs about 25 percent more to build the hemp house. That's in part because raw materials are somewhat rare and, therefore, more expensive.
But Grassroots Development President Justin Berg thinks the hemp home will bring savings over the long term.
“Paying more upfront and getting those savings over time by energy usage, you know, having a biodegradable structure. You start measuring out the materials and its impact and I think that's where we're hoping to help shine a light on it,” said Berg.
As hemp processing facilities grow in number or expand, as one recently did in Minnesota, costs of hemp material should come down, as well as giving farmers confidence in the market for hemp as a crop.
“[U]ltimately,” reporter Dan Gunderson wrote for MPR, “farmers will need a consistent market for the crop, and the construction industry will need to accept hemp as a viable alternative material. Berg hopes this research project on a tiny plot of land in Fargo, will help convince more builders and consumers to give hemp a try.”
The units, which might one day be listed on a short-term rental platform like Airbnb, will feature “hemp wood” floors and energy efficient appliances.
“The goal of this space is to bring people deeper into connection with each other and with nature,” Grassroots Development wrote on Facebook, “a place to relax and just bee.”