Here is a brief list of them: tree: good at trapping heat, visual appeal, but – it's expensive, absorbs moisture and may be deformed, need periodic painting, relatively short-lived, use of paints and impregnations often negates the natural ecology of the material. Aluminium: eco-friendly, durable, easy to use, but – with respect to roads, 'Dead', cold material in the literal and figurative sense of the word, used mainly for larger structures, such as stained glass windows, balconies, verandas, etc. PVC: environmentally friendly, durable, and retains heat well, is attractive, inexpensive, easy to use. It is no wonder that now all the most votes is given to quality and reliable windows made of wood. Numerous laboratory tests (artificial aging) and years of experience operation of window designs in the real world have proven that plastic and metal profiles differ very long service life. In particular, producers of PVC windows appreciate their service life of 50-60 years. Strength metal and PVC can talk about the advantages of a tree in front of a performance right out of window designs as dimensional stability. No deformation is to avoid distortion or cracks at the joints connection with glass. This, in turn, protects the house from uncontrolled heat loss and drafts. As is known, the window – one of the weakest elements of the house in terms of heat loss. Therefore, it is first necessary pay attention to the heat insulation properties of windows. Of course, the greatest contribution to improving energy efficiency at home or apartment makes insulation of external walls with insulation materials.