The window frame should allow the window sill to be installed horizontally. Enough space is left for the side covers. The opening should be flat, smooth, plastered or smoothed in order for the adhesive to be applied evenly.
Sufficient height of the profile must be left on the PVC windows during installation so that the window bench can be fixed without any problems. The side covers are glued with an adhesive for plastic materials, or with an adhesive specializing in PVC adhesive.
Seal the edges and places where necessary, with a silicone putty. Window benches should preferably be installed just before the last painting of the walls.