Is there such a thing as a very large foil-backed insulator board that can be cut to size for sky lights, vista view windows, and stack windows? I am concerned about sun damaging/fading the interior of the trailer if I leave the shades open. I am afraid with the shades closed the sun will deteriorate the shades themselves. If I leave the shades open and the curtains drawn I am afraid the curtains will rot. I thought about getting some 4' x 8' sheets of the insulating foam board used in building construction. Very light, but also very big and bulky for storage.