Swapping out old leaky windows with roof windows increases the energy efficiency of your home in more ways than one, so you can save money on your energy bills. Firstly, by bringing natural light into dark spaces, they allow you to keep the lights off all day long. They also invite fresh air from outside to do its own version of climate control inside, so you can let trapped heat out and cool breezes in and avoid the constant use of fans and air conditioners in the warmer months. And there is even better news: new generations of VELUX roof windows feature VELUX Thermo Technology©, which creates even better insulation during Winter months, which results in even more energy savings.