Which type of window has a sash that swings in or out like a door?

The type of window that has a sash that swings in or out like a door is known as a casement window. This design allows the window to be fully opened by pivoting on hinges, typically located on one side. This functionality provides several advantages, including improved ventilation because the entire opening can be utilized, and the ability to catch breezes more effectively when the window is open.

Casement windows are often favored for their ease of use, especially in hard-to-reach locations, as they can be operated with a simple crank mechanism. This style also tends to provide a tight seal when closed, which can enhance energy efficiency and reduce air leakage.

In contrast, sliding windows operate by moving horizontally on tracks, fixed windows are stationary with no moving parts, and double-hung windows open by sliding vertically within the window frame. Each of these designs serves specific functional and aesthetic purposes, but only casement windows exhibit the swinging action characteristic of doors.