To some extent, one could say that horizontally pivoted sash windows represent the origin of modern windows. Today they are particularly popular in the form of skylights but they are also used in large window façades since they are very easy to clean and because the exchange of air is very effective in rooms with these windows: while warm and stagnant air is discharged through the upper opening, fresh air can stream in through the lower one.

The leaf of a horizontally pivoted sash window is borne in its centre of gravity. Opening it does not require the use of springs or supporting arms. When you open the leaf you have to make sure, though, that the roller shutter function is not disrupted.