One of the products I’ve been keeping my eye on is an insulation that is made from wool remnants from sheep sheering. I’d first seen it on Building Green where Alex Wilson has written about it, but because I couldn’t find anyone who sold it in Ontario or Quebec I hadn’t mentioned it. But lo and behold, when I was in Kingston at Living Rooms, John Sinclair told me they were now supplying not just one brand of wool insulation, but two! Sheep’s wool insulation fits in with my waste theme this year. It’s a product made from material that is otherwise considered to be waste — remnants that aren’t high enough quality for use in sweaters, carpets or blankets. It is renewable, recyclable, durable and biodegradable. Some of the advantages of wool insulation are:
- It is a hygroscopic, or water loving, material. The insulation can absorb up to 40% its weight in water and still not feel wet to the touch and eliminating condensation in interior spaces filled with the insulation. This action in turn, prevents mould growth and/or rot.
- Wool is an excellent acoustic insulation.
- Memory. Wool maintains its shape and therefore its R value over time. Because of the natural kink in the fibre, when fibres are side by side tiny air pockets are created which prevent heat from travelling across the insulation.
- Flame resistant.
- Treated with borate, it is also pest resistant.
The two brands that Living Rooms carries are:
1. Oregon Shepherd Natural Wool Insulation:This product is excellent for attics and underfloor insulation, wherever loose fill insulation is required. It has an R value of around 3.6/inch. Installation: Although it can be installed by hand, using a blower will allow for maximum effectiveness of the insulation, particularly since it arrives tightly packed in plastic bags. John mentioned that they prefer the FibreForce blower by Intec for the best application.
Cost: $4.45/lb, although discount pricing may be available for volume orders. It’s best to call to confirm prices. (Prices are at time of writing, March, 2013.)
Certifications: The loose-fill insulation has the following certifications:
Contents: 92% sheep’s wool + 4% polyester binder made from recycled polyester (for maintaining shape — polyester made from recycled material) + 4% borax salt. Can be recycled, incinerated for additional energy, or composted to biodegrade.
Cost: $1.88/sqft for the 3.5″ thick batts and $2.55/sqft for the 5.25″ thick batts. Again, best to call for a quote. (Note: current pricing as of March, 2013.)
We are often asked about the methane from sheep, the answer lies in why sheep are farmed? They are farmed for the livestock industry and not the wool, the economies of wool don’t even cover the cost of shearing the sheep. Hence in an LCA [lifecycle analysis] the economic allocation is such that wool is a by production not THE product.
We have worked with a number of persons on LCAs which are not published publically at this point in time, however the foot print for wool is very low indeed. The shipping carbon cost to Canada or the USA is also low since the road miles from us to the docks are low and the carbon foot print of a container ship is also low. Sheep wool in fact locks up carbon dioxide in the growth phase and hence starts carbon negative, which compared to the man made alternatives is a distinct advantage.