The benefits of hempcrete
- Environmentally more friendly with less use of petrochemicals.
- Low maintenance.
- Exceptionally quiet from exterior and interior noise.
- Cost effective.
- Potential carbon neutral construction.
- Aesthetically pleasing with other materials (stone, wood, tile).
- Plaster invented in B.C. creates a waterproof, breathable shell around the house.
- Thermal mass assists temperature control in low and high temperatures.
- Insect and rat resistant.
- Fireproof and earthquake resistant.
- Pozzolonic vs Hydroscopic.
- Scalable cost - on par with or less per square foot than a wood frame house.
Frequently Asked Questions
How much does it cost?
Cost is a factor that people always ask about. In our experience, we have found that a single family residential house can be built for close to the same price as a custom-built stick frame house. Much will depend on the level of finishing that you want and what area of your country that you live in, etc. Also there is a question of are you building with a financial plan in mind; i.e. a rental suite or small home business/farm. This may help defray the ultimate building costs. Consider that a small building may be more expensive; i.e. 800 sq. ft can be almost the same price as a larger building, the foundation /roof, heating, kitchen , bath being the most expensive parts. Please speak with your building professional when pricing and budgeting.
Where do I start?
We offer an initial 30 minute consultation via telephone. You do need basic plans drawn up and a pre-consultation questionnaire will soon be available. In the meantime think about: How much machinery (i.e. front end loader) you have and how much free/low cost labour. Are you going to subcontract or build yourself? Also to consider the cost of the hemp shipment, how thick that you want your walls, what type of climate do you live in, what kind of structure (timber, dimensional, wood, metal) , what kind of foundation etc.
What is the R-Value of hempcrete? How does it perform in hot or cold climates?
This is a complicated question and one that is still being investigated. R-Values measure thermal resistance, or the ability of a material to resist movement of heat through it’s structure. The higher the R-value, the more the material resists the movement of heat. The R-value is a static number that does not calculate thermal mass performance.
Thermal mass is a concept in building design which describes how the mass of the building provides "inertia" against temperature fluctuations; basically the ability of the material to absorb and radiate heat or cool. In the winter, in-floor heating can provide efficient warming of the house and in a hot summer, the mass of floors and walls will keep the house cool.
Hemp walls, because they “breathe”, unlike concrete, also have a moisture regulating quality.
here have also been many tests with adobe buildings in the USA and it has been found that the total performance of the building is higher than the perceived static R-value. Hemp may have similar thermal.
In a nutshell, those living in hemp-concrete houses from the mountains in Italy to damp conditions in Ireland, have found them more comfortable to live in and less costly to heat/cool than stick/plastic/gypsum houses.
Do you have samples of your hempcrete? Can I order hempcrete?
Basic hemp recipes can be found in Steve Allin’s book, so you can mix it yourself! We do NOT supply any form of hempcrete
How long has hemp building been around?
There are projects in France now 40 years old and getting stronger all of the time, also there are some very pretty 2000 year old Roman aqueducts!
Can I visit your project?
Due to high demand for visits , we are currently only accepting consulting clients, or potential clients who have an interest in building with hemp.
Isn't hemp illegal?
Industrial hemp is NOT the marijuana plant and has been “legal” all over the world for thousands of years, and was in fact a required crop in the USA during wartime for its many textile and fabric uses. There is a theory that hemp was too much of a competitor for American cotton and timber interests and, because of it’s distant relationship to the marijuana plant, was lumped together.
Would you like to link to my hemp and marijuana supplies website?
Because of the stigma attached to marijuana, we don't associate industrial hemp and what we do with anything to do with marijuana. There is a clear distinction between marijuana and industrial hemp. The confusion between the two species is hurting the industrial hemp industry. However, once the difference is understood then it makes the industrial hemp more acceptable.
I would like to learn more about the spray-on technique. Is anyone doing this in North America?
Not to our knowledge; the cost of setup and machinery is high, and with current emerging demand for hemp building it is difficult to justify the cost.
Is there a supplier of hemp herds? In Canada? Do you know a place which sells at the retail level?
Yes, but no retail options at this point - that we know of.
How do I construct hempcrete from raw materials?
Hemp is very time consuming to process and beyond the scope of most people. I suggest contacting your local government agriculture office and get Steve Allin’s book.
How much hemp would I need for walls with these dimensions?
This is a consulting question! We are happy to help out small owner builders with details like this, but there will be a fee. We will NOT work without written plans to refer to (see above). Please have some kind of diagram in drawn up BEFORE the consultation!
How much tamping is required the hempcrete mix?
If you are pouring, as opposed to spraying, the hemp mix, you need to tamp. A stick or spade work well and some people like a sledge hammer. We tamp until the fibres are lightly compacted, but not jammed together with all of the liquid forced out.
Can I create pathways or form hempcrete into basins for catching rain water reserves for a permaculture I am setting up?
In our experience , outdoor, and in-contact-with-the-earth applications of hempcrete may not work well. Hemp is very resilient but does need time to dry out between soakings and unprotected slab applications may not work well in the long term. From Europe, we have heard reports of successful hemp-lime interior floors that have been successfully laid over a dry and drained sub-floor. The same goes for water basins. Please let us know of any trials that you have done!
What's it like to live in a hemp house?
Amazing! how many times during the storms of winter has one member of the family said “I love our little house!”. It is warm in the winter, cool in the summer, amazingly quiet and cozy- just what a house should be!
What is the most efficient way to insulate a hundred year old house with a hemp compound?
There are many ways to use hemp materials as an insulation. However one would have to would need more data; what R-value are you trying to achieve? How much of a renovation are you doing- ie tearing off old siding, gutting the place? What is the structure of the place? timber frame? Studs? What thickness? Why do you want to use hemp? What is your budget ?