The British Woodworking Federation (BWF) has re-launched its basic U-value calculation service to bring it in line with the Construction Products Regulation (CPR).

The CPR’s introduction on 1 July 2013 has meant that SMEs are required to have their U-value calculations validated by a notified body. The BWF has teamed up with the British Board of Agrément (BBA) to ensure that all calculations supplied by the BWF meet the CPR.

Chris Addison, BWF technical officer, runs the U-value service. He said: “Approval of our U-value calculations by the BBA means that joinery firms can be confident that their windows comply with the Building Regulations, secure compliance in a cost-effective manner, and of course be used for CE marking purposes.

“We work with each company to get their window to the required U-value and then issue them with a certificate, which they can use to prove compliance and promote their products’ performance.”

Micro enterprises with nine or fewer employees do not require notified body validation for U-values, but are still required to provide a U-value for Building Control approval.

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