Both sashes operate in double hungs.

1. Single-hung windows used to be the norm in construction. A single-hung window has a fixed top sash that does not operate. The lower sash can be operated vertically. With advances in materials and balancing operations, double-hung windows became standard replacements for single-hung windows.

   Features
2. The main advantage of double-hung windows over single-hung windows is that both sashes operate vertically. The top sash can be lowered, and the bottom sash can be raised to allow for fresh air. While you do not actually gain any additional open space, the options for air flow are greater. Benefits
3. Double-hung windows are also, generally, easier to clean. Because both sashes operate, they are usually designed so that they tilt in for ease of cleaning. Single-hung windows, due to their fixed state, require access to the outside and inside to clean them. This is particularly bothersome on upper-level windows. Warning
4. The one possible advantage to single-hung windows is that they can offer increased insulation from the elements. However, this is a minor consideration considering the quality of window design and manufacture in today's marketplace. Misconceptions
5. In some instances, a fixed window may be referred to as a single-hung window. A fixed window is a window that does not operate at all. It is a solid piece of glass in a frame. This is not the same as a single-hung window.