17th Nov 2010

For those now faced with implementing the new requirements under Approved Document Part L1A, Knauf Insulation is able to offer specific solutions for cavity walls, allaying any fears that this particular form of construction is at risk of demise. 

For example, a brick/block masonry wall with a cavity width of 125mm can achieve the same U-value whether insulated with high performance full fill built glass mineral wool slabs or the more problematic partial fill application using rigid foam boards.  However, by installing 150mm of Earthwool DriTherm 32, a brick/block masonry wall with a cavity width of 150mm can achieve a U-value as low as 0.18W/m2K.

David Khan, technical product manager at Knauf Insulation said: “The implementation of Part L on October 1st 2010 has the potential to reduce the house building and specification community to a state of unnecessary panic, particularly in light of the concerns in the market place of the impact upon traditional construction techniques such as masonry cavity walls.

“In fact, very efficient elemental fabric solutions for compliance with the new ADL1A can be achieved by the specification of high performance glass mineral wool products, with the resulting increase in cavity width certainly not enough to reduce the number of houses that can be built on a development, as some would have you believe.”

“There are now many variants of the two most trusted brands in cavity fill - DriTherm and Supafil - and a new generation of products are being introduced by Knauf Insulation to ensure that traditional forms of construction can quite easily meet the demands of the modern world,” concludes David. “The message is clear - don’t panic!”

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Reference: NBR158210