How to measure sliding sash windows
Storm Proof Window
Storm Proof Window

Sliding sash windows within a brick recess

Traditional sliding sash windows are fitted into a reveal or recess in the brick work, both up the sides & across the head (top of the window). There is NO recess at the bottom of the window, the cills are designed to sit on a flat surface.

When ordering a sash window you will need the total window size so it is important to take into account the amount of window sitting hidden behind the reveal. We would recommend showing approx 25mm of the outer lining of the sash box:

IMPORTANT - Check the internal width and height are larger than external. It is also advisable to expose the overall size of the window by removing the internal architraves or linings, this can be a reassuring way to ensure that the windows are the correct size.

See the first 2 drawings above showing a sliding sash window sitting within the reveal (recess).

Should you require any further assistance in measuring sliding sash windows or any other type of window, please do not hesitate in contacting one of our helpful advisors. Why not send us a few photos of your windows and we'll talk you through it!

Sliding sash windows sitting in a standard opening

New build properties tend not to have a brick recess for sliding sash windows, this is because they are designed to take spiral balance sash windows which can be fitted in a more conventional way, so the usual tight brick to brick measurement less 10mm clearance is the way to go with this. Read our standard window measuring guide for more info.

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