Along with heat reduction, window film can also help you protect your investments. Curtains, furniture and even flooring can fall victim to the effects of the sun. One of the leading culprits in fading your valuables is ultraviolet light. To keep those home furnishings and decorations looking their best, a window film with a high percentage of ultraviolet light rejection would be a good choice. Many films can now block almost 99 percent of the sun's ultraviolet rays.