The specificity of this type of windows is the use of special renovation frames with the so-called with a masking profile, which covers the wooden frame, creating a characteristic band on the inside, and from the outside, we can use special casing profiles. Cover profiles within the frames have different widths.

Then there is no need to disassemble the old wooden frames (or possibly made of other materials). The renovation frames are additionally lowered in height, so that due to the installation on the old frame, they do not significantly reduce the glazing area. Such installation avoids the risk of damaging the building facade, speeds up the time of window replacement and avoids some finishing works (repair and painting).