The BWF has teamed up with notified body the British Board of Agrément (BBA) to ensure all BWF supplied calculations can be validated for small to medium-sized enterprises to be compliant with the CPR.

Since the introduction of the CPR on July 1, 2013, businesses with 10 staff or more or with an annual turnover exceeding €2m are required to have their U-value calculations validated by a notified body.

"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 for Building Control and clients, as well as use to promote their products’ performance," said BWF technical officer Chris Addison.