How to measure up a double-glazed window unit to order replacement glass. If your double glazing becomes foggy, or the window pane has blown or cracked.

Frame Size/Opening size 440mm x 820mm (Measured from the back edge of the window beading)

Deduct 10mm from the overall width and height in most cases.

Glass Size 430mm x 810mm
Glass Thickness 4-20-4 (28mm)

0:00 Introduction
0:10 Marking the failed window
0:36 Locating the back of the window beads
0:55 Measuring the width
1:46 Measuring the height
2:38 Making deductions
3:29 Removing the window beads
5:36 Checking our measurements
9:02 Refitting the window beads
11.12 Measuring glass thickness with a caliper
11:53 Measuring glass thickness with a tape measure
12:49 Final Measurements