I just wanted to let you know that our heating oil use for this winter period is down around 30% in litres used. The difference we noticed in the evenings was remarkable and the heating was not required anywhere near as often. Clearly it is not a scientific measure of the roof’s thermal efficiency, and other factors may have affected this, but the roof has made a considerable difference to the whole house when compared to life with the draughty polycarbonate roof it replaced.