Explanation of technical characteristics

Below you can find the explanations of the technical characteristics. If you still have any questions, please send us an email or call us.  But best of all would be our master technicians explain things live to you. Book your appointment for a professional consultation.


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Thermal insulation

Uf - The thermal transmittance of the frame, or Uf, depends on the material used in the construction of the window. The lower the thermal conductivity, the lower the heat transfer. A lower thermal transmittance also reduces the risk of humid air turning into condensation in cold weather.


Ug - The thermal transmittance of glass depends on the number of panes. Most windows already have double or triple glazing as standard. Triple glazed windows offer better thermal conductivity, but pay attention to their dimensions, as larger ones can cause the window frame to fail more quickly due to their weight.


Uw - The thermal transmittance of a window tells us how much heat a window transmits per m2 of surface area at a temperature of 1K.

Sound insulation

The sound insulation, or noise insulation, of a window is particularly important for buildings located in or close to heavy traffic areas. It is not possible to avoid noise 100% of the time, but noise protection can definitely reduce the noise level.


Class 2 sound insulation or noise protection means that the windows are double-glazed. The thickness of each pane is 4 mm, while the gap between the glass panes is 16 mm and its airspace is filled with argon gas. Class 2 windows reduce noise by 30-34 dB.

Resistance class

The resistance class is particularly important when it comes to windows. In most cases, burglars cause a lot of damage to property. But worst yet is the thought of invasion of your privacy.


Burglars look for the weakest points in your home - usually old windows, which can be broken into in seconds.


Newer windows and doors are all tested for their protection against burglary. Anti-burglar window protection is particularly advised for ground floors and terraces.