UV and Solar Control Window Films Installations – Understanding the Basics Solar control window films increase the energy saving quotient of a building, contributing to both – savings in your budget and protecting the environment. Window film, which is essentially a micro-thin layer of polyester or vinyl and applied directly to glass, effectively controls solar energy, improves energy efficiency considerably and proves to be a much better alternative to traditional blinds and curtains that allow all the heat into the building. Some window films are specifically made for automotive windows. Check your local laws for restrictions before installing film on your automobile. Window films are used to meet a number of objectives like: