Sliding windows have two or more sashes that slide horizontally. Double-sliding windows allow for both sashes to slide, while the single-sliding option only allows for one sash to slide while the other remains fixed. An advantage to slider windows is their ability to adjust ventilation from being totally open (50% max) to reducing air flow to a small opening. Variations on the sliding window are: double or single tracks, screens on the interior or exterior unit, and the possibility of a pivoting hinge on the sash.
Awning windows haves top-hinged sashes that swing outward from their frame. Hopper windows haves bottom-hinged sashes that swing inward from their frame. Both variations of window types allow for direct ventilation when open and equally have low air leakage rates due to their sashes pressing tightly against the frame when closed. Like casement windows, the entire window face can be opened. Variations on awning and hopper assembly include screens to control breezes, and the choice for either vertically stacked sashes or meeting with a stile.
Sashes (Awning): Top-hinged
Operation (Awning): Outward swing
Sashes (Hopper): Bottom-hinged
Operation (Hopper): Inward swing
Variations: Screens, vertical sashes, stiles
Awning & Hopper Windows front elevation, axon
Pivoting windows are a type of window with sashes that can rotate 90°-180° around a horizontal or vertical axis usually located on or near the center of the sash. The rotation of a pivoting window allows for full ventilation, but cannot be equipped with a screen for filtering. Because of the lack of control and safety in a fully pivoting panel, this window type is generally reserved for use only in special situations requiring cleaning, maintenance, service, or emergency ventilation.
Fixed windows are comprised of a frame and a static sash. If paired with operable windows, the thickness of the fixed sash should best match the cross-sectional dimensions of the operable sash.
Double-hung windows have two or more sashes that slide vertically. Double-hung windows allow for both sashes to slide in separate tracks, while the single-sliding option only allows for one sash to slide while the other remains fixed. An advantage to slider windows is their ability to adjust ventilation from being totally open (50% max) to reducing air flow to a small opening. The sashes of a double-hung window remain held in place through the use of counterweights, friction, or pretensioned springs. Variations on the sliding window are: double or single tracks, screens on the interior or exterior unit, and the possibility of a pivoting hinge on the sash.
Casement windows are side-hinged with sashes that swing outward. Because of their outward rotation, casement windows provide significant direct ventilation and are often better suited for ventilation purposes compared to windows of equal size. Casements generally have lower rates of air leakage compared to sliding windows because the sash presses upon the frame when closing. Variations on the casement window include: interior screens to control breezes, tracks for the ends of the sashes to slide along as the window opens outward, and the option for a vertical mullion or a floating astragal connection for the sashes to close on.