Double-hung Window Hardware
The double-hung window is by far the most common type of window found in both old and new homes. The double-hung window houses two window frames, or sashes, within the window's casing. The basic window hardware found on double-hung windows consists of sash lifts and sash catches. The sash lift is typically a simple pull located at the base of the interior sash. The two components of the sash lock are typically located at the top of the interior sash and at the bottom of the exterior sash. The sash lock serves two purposes. The locks provide security and tighten the seal between the two exterior and interior sashes to reduce the amount of cold or hot air that passes between the two sashes.
Casement Window Hardware
Casement windows are far less common. Casement windows feature a single sash within the window’s casing. The sash opens outward rather than up and down as in the case of double-hung windows. The basic window hardware found on casement windows consists of casement adjusters and casement fasteners, or latches. The casement adjuster keeps the opened sash in place. The casement fastener serves the same purpose of the double hung window's sash lock. It provides security and a tight seal against the elements.