The heat insulation parameters of a window depend on many factors. The first of these is the quality of profile in which the glazing is seated. Window profiles are usually multi-chambered. The wider (deeper) the profile and the greater the number of chambers, the better the thermal insulation properties it provides. The quality of gaskets applied in the profiles is significant as well. The application of a warm frame made of insulating plastic improves the thermal insulation at the edges of the glazing. Window panes are the most important elements of a window. Their quality has a major impact on the heat insulation parameters of the whole window. Nowadays double glazing is the minimum applied, while triple glazing, which is not much more expensive, is becoming increasingly popular. Multi-chamber glazing significantly improves the thermal insulation properties of a window. Additionally, the spaces between the window panes are filled with inert gas, which further limits heat losses.

The window panes can also be covered with an additional foil layer. We call this solution safety glass or burglarproof glass. Windows panes in classes P1 and P2 are safety glass. After they are broken, they remain in one piece and protect against injury. Window panes in classes P3 and P4 are burglarproof glass, recognised by insurance companies as appropriate security, which results in the reduction of premiums.

The final factor on which the quality of the whole window depends is proper installation. Even a perfectly designed window frame will not achieve the parameters declared if installation is conducted in a faulty manner and therefore it is important to entrust this to specialised professionals.