Insulation ~ Hemp
To those yet to be introduced to the wonders of hemp, this type of insulation can seem like a hippies dream, however a simple Google search will soon lead you to the world beyond students bed-sits and Pink Floyd soundtracks to textiles, biodegradable plastics and fuel.
However, we’re interested in insulating properties of hemp, so back on track…
Description
Usually produced in batts (a precut, presized, blanket of insulation). Inorganic, non-toxic natural salts and thermoplastic binder are used to improve structure, durability, moisture, rodent & insect protection. Grown in many climates C02 is ‘locked-in’ during growth.
Features
- Non-toxic & non-irritating.
- Biodegradable.
- Renewable.
- Locks in carbon.
- Low embodied energy. Relatively little energy is consumed in its production.
- Self-supporting. In comparison to most other light-weight fibre insulations, hemp batts do not slump and therefore maintain their structure and insulating properties over time better than other comparable products.
- Note for UK readers: Hemp insulation is often grown and / or processed outside of the UK. You may want to take that into account when considering the overall ‘green’ credentials of this product.
Performance
Hemp Batts have a thermal conductivity or K value of 0.04 W/m.K.
(Watts per meter Kelvin ~ a lower value is a better result)
Lies, damn lies & statistics...
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Cost
As production is still relatively small scale, cost is high…
Representative cost:
A 75mm x 575mm x 1200mm roll of batts costs approximately £50 (rounded) including VAT and covers 5.5 m2 therefore approximate cost per square metre at 75mm depth is £9.
Other Information
An impressive statistic quoted often in information sources about hemp insulation is that for each kilogram of hemp insulation used instead of mineral wool, 1.4Kg of CO2 is saved.
References:
http://www.natural-building.co.uk/hemp_natural_insulation.htm
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Posted in Insulation |
September 6th, 2008 at 2:09 pm
I have some information on my site about hemp building materials, but your article goes into much more detail. Most of the features I knew about, but didn’t know about “locking in carbon” or “self-supporting” how great is this, I thought I was an expert but I guess your always learning, thanks for this article…I will be sending some of my visitors over for some of this info!
September 9th, 2008 at 8:03 am
I knew a hemp devotee would turn up
The carbon lock-in of all organic materials is a great feature (until that carbon is released on their destruction of course)…
Glad you found the information useful.
March 20th, 2009 at 7:10 am
Burden group are selling 100ml hemp batts for 4.04 psm. This compares with 8.16 for 90 ml rockwool! No brainer?
November 26th, 2009 at 1:43 pm
[...] most sustainable and therefore greenest category of insulators. Includes Sheep’s wool, Cork, Hemp and [...]