A cottage window is a
double-hung window — i.e., a window with two sashes sliding up and down, hung with one atop the other in the same frame — in which the upper sash is smaller (shorter) than the lower one.
The upper sash often contains smaller lights divided by
muntins
A muntin (US), muntin bar, glazing bar (UK), or sash bar is a strip of wood or metal separating and holding panes of glass in a window. Muntins can be found in doors, windows, and furniture, typically in History of Western Architecture, Western ...
(often known as a "divided light pattern" or "grille"), although in some cases both sashes may be divided.
Cottage windows are especially characteristic of
bungalow
A bungalow is a small house or cottage that is typically single or one and a half storey, if a smaller upper storey exists it is frequently set in the roof and Roof window, windows that come out from the roof, and may be surrounded by wide ve ...
or
Craftsman-style houses. It is also called a "front window".
Windows
Architectural styles
Architectural design
Architectural history
Architectural elements
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