To measure an opening for glass, measure the width at the top, middle and bottom and use the smallest, then do the same for the height. Check both diagonals, mark every socket or pipe to its centre, and tell us whether you are giving the opening size or the exact glass size. We cut to plus or minus 2 mm and confirm every order with a dimensioned drawing.
What do I need before I start?
A tape measure, a pencil and our free measuring pack. The pack has three pages: a measuring guide, a record sheet for a rectangular panel with the diagonals check, and a 10 mm tracing grid for odd shapes. Print it at 100% scale, never "fit to page", and check the 100 mm scale bar against a ruler before you use any template on it.
Work in millimetres only. A rounded centimetre turns into a gap that needs packing on site.
How do I measure the opening?
Step 1: Measure the width at three heights
Measure across the top, the middle and the bottom of the opening. The middle is where a frame or wall usually bows. Write all three down and use the smallest.
Step 2: Measure the height on both sides
Measure top to bottom down the left side and the right side. Use the smaller of the two.
Step 3: Check the diagonals
Measure corner to corner, both ways. If the two diagonals differ by more than 3 mm, the opening is out of square. Write both down and tell us when you order. Do not average them.
Step 4: Decide: opening size or glass size
Glass going into a frame or a channel needs about 2 mm of clearance on each edge. Give us the opening size and we make the deduction, or give us the exact glass size if you have already allowed for it. Say which one you are giving us.
Step 5: Measure obstructions to their centre
Sockets, pipes, taps and tiles that overlap the opening need a cut-out. Measure to the centre of each one from the same two edges every time, and say which two edges those are.
Step 6: Enter the numbers in the configurator
Type your sizes into the configurator. A drawing of your exact panel appears as you type, and the workshop cuts from that drawing. Check it before you order: it is the last point at which a number can be changed for free.
Opening size or glass size: why does it matter?
They are both valid numbers, but they are not the same number. If you give us a glass size without saying so, the deduction for the channel or profile can be taken off twice, and the glass comes out too small. Mark your figure clearly as either the opening or the glass. The one place it is usually safe to give the exact finished size is a table top, where you measure the base and add the overhang you want.
How accurate do my measurements need to be?
We cut to plus or minus 2 mm. That is why three widths and two heights matter: one figure taken in the middle can miss a bow or a slope of several millimetres. Before anything is made, you see a dimensioned drawing and tick to confirm it at checkout. Read your drawing and checks for how that works.
What about odd shapes?
Trace the shape, or a cardboard template of it, onto page 3 of the measuring pack. Mark the overall width and height, photograph the sheet flat and square-on, and upload the photo through the configurator's irregular-shape option. Our team prices it and confirms a CAD drawing before anything is cut.
Are there guides for my product?
Yes. Each one covers the details for that job, such as the shower tray lip or the shadow gap at each end of a splashback:
When should I not measure it myself?
The measuring pack is our own workshop method, not a survey. If the opening is out of square or the glass is structural, have it measured on site before you order. You can book a measuring visit and we measure for you.
Where to go next
Download the measuring pack and take your measurements.
Questions we get asked
Should I round my measurements?
No. Measure in millimetres and do not round. Use the smallest width and the smaller height you measured.
My diagonals are different. What now?
If they differ by more than 3 mm, the opening is out of square. Write both diagonals down and tell us when you order, or book a measuring visit.
Can holes be added after the glass arrives?
Not in toughened glass. Every hole and cut-out is made before toughening, so measure your fittings and obstructions before you order.
What tolerance do you cut to?
Plus or minus 2 mm, and every order is confirmed with a dimensioned drawing before anything is made.