Mestre Raposa respects especially the need of heat protection, noise abatement and against the intrusion as a mark of quality. While a high thermal insulation and passive use of solar energy contribute to energy saving, the acoustic insulation contributes to the improvement of living conditions. In this context appear new regulations of energy certification concepts like "the Coefficient", g Factor and coefficient U (previously designated coefficient K). Here's what it means:
This coefficient indicates the amount of air (m3), which passes between leaf and frame (linear m), divided by the difference in pressure of 1 kp/m2.
The resulting value indicating the permeability of the doors and windows at the joint between the sheet and the rim. The higher this value is, the lower the door or window seal, by which there is a high heat loss as well as a low sound insulation.
Glass = solar Factor g
Through this factor measures the solar energy transmitted to the inside through the glass. This means that the doors and windows are not only constructive elements that originate from thermal losses, but also produce thermal gains through the incidence of solar rays. This means that the higher the solar factor (g) and the greater the isolation provided by frames is, the smaller the heating costs of the building will be. In modern double glazing the g factor is approximately 0.6, that is, 60% of the Sun's rays enter inside the building. Therefore, in large glazed openings must be expected solar protection.
The thermal losses of a window are evaluated by the coefficient U, which indicates the amount of heat that escapes, in an hour, to the outside through a window (per m2), and assumed a difference of temperature between exterior and interior of 1º C. The metals conductors has a U coefficient higher than the insulating materials. This means that the smaller the coefficient U, will have a lower power loss and a better insulation is provided by the window, so that less energy is wasted. The value currently reached nowadays is 0.9 W/m2.K.
The insulating glass is composed of two or more glasses with a special gas filling in the space between them and with a stainless steel separator which reflects heat. Exterior joints of glass are sealed with a special product that isolates the moisture and air, this glass, associated to profiles with multiple air chambers and the isolation of these systems allows optimisation of the thermal insulation.