Because of the direct mounting of the window sill bracket to the window, it is irrelevant how far this extends into the insulating layer. The window sill end piece lies directly on the mount. Through the screwing or sticking of the window sill end pieces to the window sill bracket, loads from below (e.g. wind load) are also carried.
Up to a length of 1,000 mm and an overhang depth of 240 mm, it is sufficient to place one window sill bracket on the left and right. In case of longer window sills additional fixtures must be applied underneath at a maximum interval of 900 mm.