Definition of a Sash Window

A hung sash window

While a window sash consists of the glass and framework holding it, a sash window is generally constructed of two or more sashes inside a window frame.

Function

Some sash windows do not open, particularly in commercial buildings, but most residential windows are constructed to enable one or more sashes to be opened.

Double-Hung Sash Window

A double-hung sash window consists of two overlapping sashes that may each be opened by sliding up or down with the aid of counterweights or springs.

Single-Hung Sash Window

In a single-hung sash window, one sash may be opened while the other remains stationary. Either the top sash or the bottom may be moveable depending on construction.

Horizontal Sash Window

The sashes in a horizontal window slide open on a track inside the window frame. In many sliding windows, only one sash moves while the other is fixed in place, but there are double sliding windows available that allow both sashes to open.

Problems

Although sash windows constructed of wood may be aesthetically preferable, wood windows do require more maintenance than windows made with other materials. Humidity and other weather factors can cause wood to crack or warp.

References

• Ask the Builder
• Charlotte-Mecklenburg Historic Landmarks Commission

Resources

• Old Home Journal