Design of windows and doors, as one of the main elements of building envelope, have a direct impact on creating the necessary climate and ensuring hygienic conditions in premises rates one-time costs and operating costs and the formation of the architectural appearance of the building as a whole. It is known that, of all types of building envelope windows and doors have a minimum value of resistance heat transfer and air permeability and are the main sources of heat loss in buildings. During the cold period of time heat loss through the wooden windows can be as high as 40% of the total heat loss of the building. Therefore, improvement designs of windows and doors, improving their thermal properties is of great economic importance. The bulk of the buildings constructed on the model projects, is equipped with windows with dual glazed windows in separate paired wood bindings, and in some cases – with a three-layer glass in a twin-separate bindings. Estimated value of resistance heat is widely used wood windows with dual glazed windows amounts to 0.39 m2 0S/Vt, but with three layers – 0,53 m2 0S/Vt.
However, the actual thermal engineering quality of such structures, due to defects in individual elements, significantly lower than estimated and therefore does not meet the requirements of energy supply and normalized parameters of the microclimate and comfort of indoors. Real opportunity to significantly reduce heat loss through eurowinows wood provides the introduction of new energy efficient windows. Problem Solving heat and sound insulation of the premises with double glazed windows in wooden bindings nearly impossible. Switching to a three-layer glazing wooden windows, as one of the main measures to ensure energy conservation in buildings, will not make the proper economic effect, since it requires a significant increase in consumption of wood and glass and, consequently, the cost of construction. Improved thermal barrier qualities of windows is only possible by fundamental change in their design decisions and the use of new efficient materials and products, as well as improved building codes and design rules. In Western Europe and the U.S. for ways to reduce energy consumption in buildings have been actively sought in the 70's in connection with the emergence of the oil crisis and soaring energy costs. In this regard, have been developed and implemented industry new types of windows with binders of polymer materials and the light transmitting elements of glass having a high value of heat transfer resistance.