fanlight windows open at the back of the house.
The part-glazed door is surmounted by a 4-pane fanlight.
By opening a fanlight does not loose heat in most cases but actually circulates the heating around the rooms more efficiently.
High wall sealed unit double-glazed timber window with arched fanlight to half landing.
HALF LANDING With full wall sealed unit double-glazed multi-pane window with top fanlight.