Sheep’s Wool for Insulation?

Originally published 9/25/2015

Sheep in field

Wool has some unique properties that make it one of nature’s most amazing fibres!  If you are building a small home, we recommend giving sheep wool insulation some examination. Here are some top reasons why:

Air Purifying – Natural sheep’s wool actually absorbs and filters toxins from the air around it– indefinitely. Doing so, gives wool the edge in home odour control and whole home health for the dweller. No man made products do this, at least none that we could find.

Non-toxic – Sick building syndrome and allergies are a growing concern for many people as the processes and chemicals used to make the modern insulation materials are often toxic to some people. Wool is non-toxic during insulation and at rest. Also without irritating fibres!

Dehumidifying – Wool fibres are hygroscopic. That means wool is able to absorb a great deal of moisture (30-34% of its own weight) and release water as a vapour in the air; not trap it. Fibreglass can’t do that. Further, as wool fibres absorbs moisture, they generate tiny amounts of heat. This acts to prevent condensation in construction cavities by maintaining the temperature above the dew-point in damp conditions.
It basically offers your home the excellent breathing that it needs, aiding in the filtering/purifying effect and regulating humidity.

Fire resistant – Surprised? We were too until I ordered some samples and tried this out. It doesn’t burn easy— less so than conventional man-made materials in fact.  It is just about the only natural animal fibre that resists ignition from a flame, requiring over 570-600°C to do so.  As soon as a flame is removed from wool, it will actually smoulder and self-extinguish very quickly. Man has spent a lot of time in the lab to do this for other petroleum based insulation materials– and often without the same success rate as nature has given.

Sustainable & Renewable – A 100% natural product with no harm to the animal that produces it. Harvesting and processing sheep’s wool requires a fraction (less than 15%) of the energy to produce or worker hazards to those that produce it compared to  man made equivalents. A sheered sheep only has to let time happen for the return of its wool.

Great Insulation Factor – Sheep’s wool does offer excellent insulation properties nearly on par with other insulation, in some cases better. Sheep have been able to survive the harshest elements for thousands of years.  Wool coats on Earth’s creatures protect them from extreme cold and searing heat, so why not you in your home?  We won’t go into all of the science here. If you want to learn more, see the link below.

Sound Dampening– With millions of tiny air pockets that trap air, helping to provide a thermal barrier, there is also a huge gain for sound dampening.

Resistant to mould, insects & pets– Clean and purifying, wool is not prone to attracting any unwanted home dwellers!

Resists settling You can be sure it stays where you put in behind walls, floor or ceiling.

Other considerations: 
In Canada, there are not a great deal of companies that process and sell wool insulation for constriction purposes. We ordered our samples from the UK.  The company we ordered from had reasonable prices even with shipping to Canada. The samples were free.
Wool insulation can come at a much higher cost than standard, mass produced materials available nearly everywhere.  Cost has to be weighed out in one’s plans; however, being that smaller homes require less materials, using wool may be done on a reasonable budget.

We are not suggesting wool is the solution for every home build, only that we encourage folks to look into it as a viable option when procuring materials. It realy is an amazing fiber.