Sash
A sash is a glazed part of a window or door assembly that opens for purposes of ventilation, viewing out, etc.
In a casement window, the sash is the hinged part of the window (within the frame) that opens outwards or inwards for ventilation. It is the part which holds the glass in position in a secondary frame within the main window frame.
In a traditional sliding sash window, the sash is the glazed part which slides vertically to allow ventilation, views out etc, and holds the glass in place. Such windows usually have two sliding sashes.
For more information see: Window.
The term sash can also be applied to doors which incorporate glass, i.e the hinged part of a door assembly which opens for entry and exit and which is either fully or partly glazed. When a door is not glazed, the opening part is usually called the ‘door leaf’.
NB Short Guide, Fabric Improvements for Energy Efficiency in Traditional Buildings, published on 1 March 2013 by Historic Scotland, defines a window sash as: ‘The timber frame around the glass in a window. The term is used almost exclusively to refer to windows where the glazed panels are opened by sliding vertically, or horizontally hence the term sash and case window.’
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