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Articles and Further Information

The “Sheep” Alternative to Rising Energy Bills…

The increase in heating bills throughout the country has prompted more and more people to discover alternative ways to either heat their homes using cheaper sources of fuel, or improve the standard and amount of insulation in their homes in an attempt to bring down those ghastly quarterly bills. And with 50% of the UK’s energy being used within our homes, the Government is also keen to see energy use in buildings reduced, and are therefore promoting a number of programmes to encourage increased insulation in buildings.

There are a large number of different insulation products on the market and this tends to leave most consumers in a state of confusion over which one to chose and why. In the past, it was normal to use natural products for insulation, but recent years have seen moves to synthetic, often toxic products that have known health risks including Man Made Vitreous Fibre (MMVF), a product that in the USA is considered “reasonably anticipated to cause cancer in humans”.  It is thought that over 60% of homes in the UK have MMVF particulates in their homes. These products are not only unhealthy for people but also have a damaging impact on the planet as they use huge amounts of energy and chemicals in their manufacture.

There are now many natural alternatives that are safe for your family and are produced in an environmentally friendly manner. All natural insulations are made from renewable plant or animal sources, for example, recycled paper, flax or sheeps wool, and use very little energy in their manufacturing process. They are also safe for installers and are re-usable or even biodegradable at the end of a building’s life.

Natural insulation has been installed in a building the benefits are has noticeable beneficial effects. It has an ability to “breathe”, meaning it can absorb airborne moisture and release it again when the air is drier, keeping the relative humidity in a building stable and comfortable for residents. All dwellings have differing levels of airborne moisture resulting naturally from human activity and the weather. The ability for natural insulation to “breathe” does not affect its performance, for example, Flax can absorb up to 25% of its weight in water before starting to lose its thermal capacity and sheeps wool insulation can hold up to 40%.

Natural insulation products are ideal for use in “breathing” constructions, both in older buildings constructed using traditional techniques such as stone, cob and timber and new sustainable builds such as straw bale buildings.  These products protect the building structure from the damage that can be caused by condensation and moisture. This is especially relevant in timber constructions as the insulation acts as a “wick” and pulls the moisture away from the wood.  

Additional benefits of natural insulations are its effective sound insulation properties, its ability to perform over time and in the case of sheeps wool, improving indoor air quality by absorbing pollutants including many volatile organic compounds (VOC’s). A common VOC that pervades throughout buildings is formaldehyde, which is released from a variety of processed materials such as pressed wood, medium density fibreboard, treated fabrics on furniture and some paints. The unique structure of wool allows it to bond with many potentially harmful substances, especially formaldehyde, which is permanently locked into the wool fibre, rendering it useless throughout the life of the insulation. In laboratory tests, formaldehyde levels of approximately 5 parts per million were reduced to near zero within 20 minutes with no re-emission at 30 degrees. The importance of this is very clear when you discover that exposure to formaldehyde can produce sensory and respiratory effects even at extremely low concentrations in the air in your homes.  Natural insulation is proving to be better for us as well as our environment.

By Anne Humphries
Manager of the Sustainable Building Resource Centre