17.3.1 Fixed window
It is fixed in the wall and makes no provision for natural air circulation.
17.3.2 Double hung window
In this type, both sashes slide vertically with the weight balanced by the sash weight, spiral springs or tape spring balances.
17.3.3 Horizontal sliding window
In this type, either one or both sashes are arranged to slide horizontally. Sashes are sometimes suspended from rollers operating on overhead tracks. Heavy sashes are often provided with nylon rollers at the bottom for ease in operation.
17.3.4 Casement window
Any hinged window, which may swing out or in like doors, is termed as casement window. These windows usually swing on extension hinges provided on the sides. There are out-swinging and in-swinging casement windows with two sashes. Extension hinges are used to make the sash swing clear of the inside surface of the wall.
17.3.5 Folding window
It is a form of out-swinging casement window with the two sashes hinged together on its meeting stile, rather than each to its outside stile. The projection arms are so arranged that the sashes operate symmetrically.
17.3.6 Pivoted window
Horizontally pivoted sash windows are often arranged in a row to form a continuous window in a sawtooth roof or monitor and they operate in harmony from the floor by a mechanical operation.
17.3.7 Top- and bottom-hinged window
Sash windows may be top-hinged out-swinging or top-hinged in-swinging or bottom-hinged in-swinging type.
17.3.8 Projected window
A window with a ventilation sash that projects outwards or inwards is called a projected window. In this type, the ends of the arms are pivoted to the side of the sash and to the frame.
17.3.9 Hopper window
Any inward projecting window when located at or near the bottom of a window is termed as hopper window.