VELUX is concerned that if the Green Deal fails to win the confidence of consumers it could be a 'kick in the teeth' for the wider energy efficiency retrofit market.

“We have also made adjustments to a product’s performance by considering a variety of in-use factors that can affect the way they operate,” he said.

Support from local authorities and a push on take up of the scheme by entire roads rather than individual properties were discussed as ways of reassuring SMEs of demand.