Single Hung and Double Hung Windows
Depending on the weather and climate in the area you live in and the style house you own, you may have either double-hung windows or single-hung windows. These two types of windows can look very similar if you don’t know what to look for, but knowing which you have is important. The operation of the bottom sash is almost always guaranteed in sash windows, but in a single-hung window, the top sash is stationary. It can be removed easily, but it is not designed to be operable like the bottom sash. In double-hungs, both sashes are operable.