Unplasticized Polyvinyl Chloride is a building material valued as a great alternative to painted wood. It owes its popularity to low-maintenance, high cost-effectiveness, and appreciable longevity. Used in doors and windows it is known as a money and energy saver thanks to its very good insulation, durability, sunlight- and weather resistance. Because UPVC windows are relatively cheap, they are considered to be a great choice for installing double-glazing. In addition, it is not in danger of decomposing biologically.