Single hung windows look almost identical to double hung windows. Both have an upper and lower sash, traditional aesthetics, and are easy to operate and clean. The key difference between these styles is that both the top and bottom sashes of a double hung window are movable. Only the bottom sash operates on single hung windows.
Single hung windows are ideal for areas where the top sash might be difficult to reach. Because of their fixed top sash, single hung windows prevent more air infiltration than similar double hung windows and are more energy efficient. Additionally, single hung windows may be less expensive.