The properties of wool

Wool has a very complex chemical and physical structure, which accounts for its uniqueness and versatility as a textile fibre. The fibres are made up of more than 20 amino acids, which combine to form long chains (polymers) of protein.

It's the internal structure of each woollen fibre — a three-dimensional corkscrew pattern, or helical 'crimp' — that gives wool its elasticity. The coiled springs of these molecular chains, with their permanent built-in 'memory,' makes the woollen fibres themselves coil-shaped and accounts for their enduring resilience.

Wool is superior to all other fibres in its ability to handle body moisture in both warm and cold environments. The porosity of the cells in the outer layers of wool fibre allows them to quickly and efficiently absorb and evaporate moisture. The fibres can absorb up to 30% of their weight in moisture — ten times as much as any synthetic fibre — without feeling damp or clammy. These properties are why wool is an excellent thermal insulator, not to mention the mesh of the fibres, which creates millions of air pockets that further help to regulate temperature and humidity.

Wool is a naturally strong fibre. It can bend back on itself 20,000 times without breaking. Compare this to cotton at 3,200 times, and silk at 1,800.

Due to its unique chemical structure and natural moisture content, wool is naturally fire-resistant. And despite its natural moisture content, wool's dry, porous nature repels mildew and dust mites. 

Sheep wool insulation does not burn

Sheep wool doesn’t burn; it is just about the only fibre that naturally resists flaming, and as soon as the flame is removed, it will self-extinguish.

As a result of the wool’s high nitrogen content, it will merely smoulder and singe away instead of bursting into flame. You will need to heat the wool to a temperature above 560°C before it burns.

Sheep wool doesn’t itch.

Sheep wool insulation is a breeze to work with, as it is safe and harmless.

We believe that the majority of people will want to insulate their lofts as part of a DIY job, so the fact you can easily handle the sheep wool makes the job far simpler. It is important to stress though, that if you are in any way uncomfortable with trying to insulate your loft, please get in touch with a professional to carry this job out for you.