The sashes are the moving glazed frames; the case is the fixed surround in which they slide. Traditional cords run over pulleys to concealed weights that balance the sashes. Knowing these names makes a repair enquiry easier to explain.
The main components
- Sash
- The moving timber frame containing the glass. A typical window has an upper and a lower sash.
- Case
- The fixed timber assembly around the sashes, with space for the traditional weight mechanism.
- Meeting rails
- The horizontal members that meet where the upper and lower sashes overlap when closed.
- Sill
- The lower part of the window assembly, including the exposed surface that sheds rainwater outwards.
- Parting bead
- The narrow strip separating the channels in which the two sashes move.
- Baton rod or staff bead
- The inner retaining strip; terminology varies between trades and regions.
- Cords, pulleys and weights
- The traditional counterbalance components. Some windows use chains instead of cords.
- Glazing bars
- The timber members dividing a sash into separate panes.
For background on the traditional construction, see Historic Environment Scotland’s sash and case window guide.
Describe the location as well as the part
You do not need to know every joinery term before contacting a specialist. “The bottom sash of the front bedroom window drops when opened” is more informative than “the window is broken”. If a name is uncertain, mark the location on a photograph or describe it in everyday language.
For multiple windows, add a room and position reference. From inside, identify left and right consistently. Note whether you are describing a moving part, a fixed frame section, the glass or the joint with the surrounding wall.
Does every sash window have the same mechanism?
Do not assume that fittings or opening methods from another window will apply to yours. Alterations, replacement sashes and different generations of hardware can change how a window works. Ask the surveyor to identify the mechanism before ordering replacement parts or trying a cleaning feature.
What are Simplex fittings?
Simplex is a term you may encounter when discussing inward opening arrangements for cleaning traditional sash windows. Do not assume that any sash can swing inwards. Ask a specialist to identify the fittings, confirm their condition and demonstrate the correct method for the actual window. Do not release retaining parts on the basis of a generic online description.
What should you send with an enquiry?
Include an overall interior photograph, a close view of the fault taken safely, the approximate size, the floor level and a description of what happens. Avoid dismantling the window to expose a hidden component. The inspection can establish the terminology and the repair specification.
Related advice and services
Back to all sash window resources
Discuss your windows
For a property in Stirling or Central Scotland, contact The Sash and Case Window Company with photographs and a description of the problem. An inspection can establish which work is appropriate for your windows.