Image credit Oregon Shepherd
It is common in New Zealand and a luxury in the UK, but now sheep wool insulation has come to America, via Oregon Shepherd. There is a lot to love about this stuff; "This all-natural and inherently fire-retardant material is non-toxic, resists mold growth, is vermin resistant and is acoustically superior." After all, sheep know a thing or two about keeping warm.
"Our Sheep Make it All Possible And We Take Pride in Keeping Them Well Cared For!"
The company lists a number of significant benefits:
The unique advantage of wool as an insulator is the NATURE of the fiber.
- It absorbs and desorbs moisture, it heats and cools as this process takes place. Wool therefore can absorb moisture in your house, preventing condensation.
- It has plastic memory, not that there is any plastic in wool, but rather that technical description is used to explain the "crimp"; the ability to retain the shape it was in before it left the sheep.
- The energy required to produce our insulation is less than 10% of that required to produce traditional insulation materials.
- Wool can absorb and breakdown indoor air pollutants such as formaldehyde, nitrogen dioxide, and sulfur dioxide.
- Wool is a sustainable and renewable resource; every year our sheep grow a new crop.
- Wool is completely recyclable; at the end of its life as insulation it can be remanufactured, reused, or biodegraded.
- Wool is an excellent absorbtion medium of sound waves; its inherent qualities provide much more acoustic insulation than traditional insulation in similar applications.
- While wool is generally fire resistant, our wool is treated with a 100% natural solution of organic materials that provide unequaled fire and vermin resistance. These materials are bonded chemically to the wool fiber, not merely "glued on" as in most other insulation products.
Installation by spraying
I am always a bit worried about those additives, but Alex Wilson of BuildingGreen looked at the stuff last year and explains what they have done:
Oregon Shepherd enhances wool's inherent fire-retardant properties with a borate additive. The company uses a proprietary formulation using a natural protein to covalently bond the borate compound to the wool fibers. The material has been tested to ASTM E-84, E-1496, and C-518 standards, and passes with flying colors, according to Workman.
Along with increasing the material's fire resistance, the borate provides insect resistance--eliminating concern about moth infestations, for example.
He concludes that " The product looks like a winner!"
Costs appear to be about twice that of fiberglass, slightly higher than cellulose and competitive with cotton. This might be the perfect insulation for the hypersensitive.
More at Oregon Shepherd, found on Materials and Sources.
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