HempWood as a flooring material
We are about 1/3 into the build of our downsize home in TN and are researching flooring materials for our approx 2000 Sq Ft home. We have family with allergies and eczema and were looking for materials for the floors with the least potential concerns. I searched GBA but could not find articles on hemp as a flooring material and then was surprised to find a manufacturer in our backyard about 75 miles away in Murray KY. The sales persons seemed very knowledgeable about the allergy issues and how the hemp made into flooring planks would not cause issues. He provided information on their website https://hempwood.com/ concerning their environmental impact and chemical issues.
Does anyone in the community have experience with this flooring product? We are installing on an insulated concrete slab in Zone 4. They say the floor can be floated with perhaps a vapor barrier product being applied to the concrete to stop moisture migration through the concrete.
Any advice is appreciated. We like the idea of getting our flooring from a local source but just don’t know enough about the material.
Thanks
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I have no experience with Hempwood, but cannot imagine a product bonded with glue would be better for chemical sensitivities than a solid wood floor.
I have no experience with that product but their website says that their products are CARB-2 compliant, meaning they have very low VOC emissions, including formaldehyde. Natural wood contains and emits formaldehyde, though I'm not sure where it falls on the CARB-2 scale.
The initial quote for the basic flooring product is 6.49 per sq foot, which seems in line with other engineered flooring products. The sales person indicated the founder worked in the bamboo flooring industry and had a problem with formaldehyde, thus he ensured this product would have none. Our TN hemp industry started with a bang a few years ago with the CBD craze, and a lot of farmers got taken by the producers. This product apparently is derived from the woody stalk and the rest is biomass used to provide heat and energy for the facility. If this product performs, it would seem to be a step forward, but I wanted input from some building science minds as I remain skeptical.
I wanted to update this post to provide an update on our project. We researched further and decided to try the HempWood laminate flooring. It was not the least expensive but we were able to get the install done with a local installer in communication with the manufacturer.
Here was our experience:
1. The flooring material was manufactured within 100 miles of our house build site. The manufacturer had reclaimed tobacco warehouses and hemp/CBD storage facilities after the CBD market bubble broke and the local farmers took a big loss.
2. The manufacturer was easily accessible and open to questions and indicated the entire life cycle of the product and the associated engineered plywood flooring. The goal was to use low VOC components and a low impact manufacturing facility. From my visit to the facility when I picked up the flooring, they have achieved that.
3. We had to get a local flooring installer to agree to lay the floor, as a favor, as many installers have not had experience with HempWood flooring. Due to good communication all around, the process went well and we are quite pleased with the result.
4. We have not experienced any issues with smells or other chemical issues with the floor. The surface is VERY hard (harder than hickory or a standard scale) and after a month we have no scratching issues from our pets at all.
5. The cost is not competitive with many options. We paid 7.99 per sq ft for the flooring itself and with our choice of a zero VOC adhesive over the concrete slab and labor/prep we ended up paying around 12.00 per sq foot. It became a splurge in our build but as mentioned we are very pleased with the look and performance of the floor thus far
In summary, we are convinced this is a sustainable flooring alternative that for this area (Middle TN and KY), carries a low carbon footprint compared to the alternatives. It is unique and time will tell how it performs.
Thanks for the prior comments on this product while we were deciding.
QH
Longstory,
Thanks for coming back with an update. It's rare we get to hear how things turned out, and I'm particularly glad your experience was a good one.
Pictures attached.
That material has a nifty weathered look to it. It will be interesting to see how it holds up to traffic over a few years' time. Nice looking floors!
Bill
Several of the tradespeople in the finishing of the house said they had never seen a floor like this. And the finish is not slick, so you don't tend to slip on the surface.
Thanks
I found this article on hempwood floors.
https://buildingrenewable.com/pros-and-cons-of-hemp-wood-floors/
The only downsides I see is that it has to be kept dry (which might be difficult on a concrete slab) and you have to be careful about how you clean and maintain it.
Thanks for the link. I had not seen that and overall it reflects our experience with the product. One thing I did not realize is that the owner and founder of the company mentioned is very hands on. He came to our house after it was finished and we moved in to inspect and make a minor finish touch up himself. He was very positive about the future of the material, and said they are continuing to innovate to reduce the cost. He indicated that green building initiatives and health concerns had increased the number of installs in federal buildings and schools. So time will tell if this material is going to make it as a mainstream flooring product. As hemp can be grown in so many areas and is so easy on the environment, I hope it can be competitive.
Did you lay the hemp wood directly on top of the concrete or is there a substrate in between (I.E. one of those OSB subfloors that has the raised plastic dimples on the underside to provide an air-space)?
I just watched a video on Youtube from Corbett Lunsford called “The Science of Sick Building Syndrome and Environmental Sensitivity” and they mentioned that most people with chemical sensitivities also have mold sensitivity.
https://www.youtube.com/watch?v=RHT71u1ipbo&t=20s
I’d be concerned with mold forming under the hemp-wood flooring if it’s directly on the concrete without there being an air-space because despite the slab being insulated moisture could still condense on the cooler concrete surface and you’d never be able to see it.
Thanks for your thoughts on this and the answer is there is no substrate in our build. Moisture sensors were placed on the concrete in several locations and left for about 2 weeks to ensure it met the recommendations for the manufacturer (attached). The concrete was poured over 4" of foam insulation with a plastic vapor barrier under the concrete. A zero VOC adhesive was used to lay the floor.
I was assured the conditions were good for the install but you can never be certain. I did note the stringent requirements of the manufacture concerning installs over concrete, as your concerns point out. If there is excessive moisture then we will likely get warping/mold and then we will have a major hassle to repair it. I hope physics is in our favor on this one.
Thanks
In fairness to that hempwood material, bamboo floors have similar moisture sensitivity. The usual "solution" I see over concrete is to use a thin underlayment under the floor. With Cali's bamboo flooring, their "Cali Complete" product is commonly used. That material is about a 1/8" foam with a foil facer that gets taped. The end result provides a little bit of give to the floor (less of a "hard" hard floor feeling when walked on), a bit of insulation, a bit of sound deadening, and a vapor barrier from the taped facer. There are other similar products out there too.
Bill
This may not apply to your installation, but if you glue down a wood floor to a concrete slab and the manufacturer says that any moisture in the slab (or excess humidity in the room) will not cause mold to grow and affect the wood do they also consider how mold growth will affect the glue? Can the glue be "food" for mold?
Thanks for these ideas. I know that our installer had phone communication with the manufacturer (actually the founder/owner) and they discussed best practice for the concrete floor installation. The moisture readings were within parameters apparently so they decided not to apply a vapor sealant to the top of the concrete before laying the floor. The glue was a zero VOC product as specified in the manufacturer install sheet attached above. More expensive than I expected (over 2,000.00 for the 2400 sq foot install).
Our builder did not raise concerns with the concrete due to the vapor barrier applied underneath and the foam insulation as well.
Time will tell but we can only hope at this point. I perhaps should look into a monitoring system for mold? Anyone aware such a monitor exists as part of the indoor air quality movement?
Thanks all
QH