Insects and Durability
Because sheep’s wool is naturally susceptible to clothes moths, it must be protected to ensure long-term integrity. All Thermafleece wool is treated with sodium borate (borax) fire retardant and is not susceptible to clothes moths without the addition of biocides.
The Borax Treatment Process
- Complete Impregnation: Every wool fibre is immersed in a borax solution during processing to ensure total coverage.
- Natural Protection: Because of the concentration of borax used, Thermafleece is not susceptible to moth attack and does not require additional organic biocides.
- Scientifically Proven: In UK laboratory assays (BS4797/ISO3998), the common clothes moth (Tineola bisselliella) was unable to damage treated Thermafleece wool even during extended exposure periods.
Durability and Longevity
Borax is a well-documented preservative that has been used in the construction industry for over 50 years.
- Lifetime Protection: Under normal service conditions, the borax remains within the wool fibres and provides protection for the entire life of the insulation.
- Stable in Dry Conditions: Borax is water-soluble but does not “leach” or evaporate under normal circumstances.
- Resistance to Moisture: While transient condensation on the surface poses no risk, the treatment only becomes vulnerable if the insulation remains completely saturated for long periods.
Important Note: As with all natural fibre products, this insulation is intended for internal environments. It should not be used in areas where permanent moisture build-up is expected.
