Houses can lose a vast amount of heat via window glass but you dont need to fit costly double glazing or keep curtains drawn to lower winter heating costs or to be more comfortable in summer thanks to our insulating window filmtests have shown that this nearly invisible insulating film adheres to the glass to reflect heat back into the room in winterin summer it has the reverse effect blocking 65 of the suns thermal energy and 97 of uv light to keep your home cooler and more comfortabl