5 July 2002

WARM OUTLOOK FOR

LOW GRADE WOOL

A Cumbrian farmer is getting

a warm reception for a new

product using low-grade

wool, reports

Michael Edwards

THE market for low-grade wool has always been restricted, so much so that some hill farmers recently burned their fleeces. However, there might now be a brighter future for fleece from hill sheep like Herdwick and Swaledale, thanks to a Cumbrian farming family.

Christine Armstrong, with assistance from her partner, David Baldry, of Cote Farm, Dacre, Penrith, has set up her own company, Second Nature UK, to develop Thermafleece, an environmentally friendly building insulation material that has been well-received by the trade. So confident is she that an ambitious £2m annual sales target is predicted by 2005.

"Ive been involved in farming all my life," she said. "I fully understand and have personal experience of the despair currently felt throughout the industry. We believe that it is right to send out clear messages throughout Europe that British agriculture is not giving in.

"I liked the idea of doing something with such a natural product. In the 18th century people used sheeps wool for insulation so I began looking into whether it could be used now."

She took her idea to Leeds University and after a couple of years research managed to get the product to market.

The coarser fleeces that are not in high demand in the international woollen textiles market are used to create a non-woven wool blend with excellent insulating properties, comparing favorably with other fibrous insulation materials. However, because wool is a natural fibre from a fully renewable resource, the product life cycle has an ideal energy balance; the Thermafleece manufacturing process expends only 14% of the embodied energy used to make glass fibre insulation, thereby paying back manufacturing energy costs seven times faster.

The new product requires no protective clothing during installation, does not irritate the skin, eyes or respiratory tract and meets all current building and safety regulations. Thermafleece is also totally recyclable for use in other environmentally friendly ways at the end of its useful life, which is predicted to be in excess of 50 years.

&#42 Thermafleece

Christine explains: "We have not developed Thermafleece to be a cheap alternative to other insulation materials such as glass fibre. In fact it costs significantly more. Specifiers and builders who have shown interest in our product see added value in its ecologically sound nature and in the extra benefits wool brings to a buildings environmental performance including summer cooling, winter warming and condensation control."

The fleece, used by the National Trust in Yorks, has also been installed in Newcastle City Councils new energy efficient classroom at Tyne Riverside Country Park, while Court Primary School in Chard, Somerset, has had Therma-fleece fitted as part of a £600,000 make-over. Christine is also fitting out her own farmhouse with the product.

To meet the strict requirements of building regulations and British Standards, Thermafleece had to be capable of resisting insect attack as well as being fire resistant. Most wool insulants use Boron salts to perform this task – a chemical additive which often costs as much to use as the wool itself, because its toxicity creates major waste-treatment problems. It soon became clear that finding a low-cost, effective but environmentally-friendly alternative insecticide was going to be essential to the success of the product.

Approaches to various research bodies finally produced the holy grail – a dry, environmentally-friendly alternative to insecticide, that is now the companys patented secret "pixie dust".

&#42 Complex structure

The fibres used in the manufacture of Thermafleece naturally form a complex but low-density structure, with microscopic scale-like surfaces, enabling the insulation to trap large volumes of air. These thermal and structural properties are complemented by the products ability to absorb and release up to a remarkable 40% of its dry weight in water vapour; so, as temperatures fall and the dew point lowers, water vapour is absorbed, generating heat as it does so.

Another interesting fact is that wool has a natural tendency to melt away from flame and self-extinguish, so only a conventional fireproofing agent is added to meet the BS5803-4 Standard for fire resistance.

The scope for Thermafleece seems promising and Christine is already developing further ideas which might benefit from the material.

Inquiries Second Nature: Tel: 01768-486285.

Christine and David have found a new market for fleece from their sheep and have set a £2m annual sales target.