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To measure for a glass shelf, measure the span between the supports first, because that sets the thickness. Then measure the alcove at three heights if the shelf sits in one, and decide the depth. Order 3 mm to 5 mm under the smallest alcove figure, or give us the opening and say it is an opening, so the shelf can go in.
What do I measure?
| Measurement | Why it matters |
|---|---|
| Span between the supports | Sets the thickness. Sag grows fast as the span gets longer. |
| Alcove width at three heights | Walls lean. The narrowest figure is the one that fits. |
| Depth | Wall to front edge. Choose it for what goes on the shelf. |
| Load | Books along the length, one heavy object, or a row of bottles. |
The configurator asks for a width and a height. For a shelf, enter the depth from the wall as the height. You also choose the glass, the thickness, the corners and any holes. Shelves have polished edges all round.
How do I measure it?
Step 1: Measure the span
Measure bracket centre to bracket centre, or the clear distance between two channels. It is often 100 mm or more shorter than the alcove.
Step 2: Measure the alcove at three heights
Measure across at the height the shelf will sit, then 100 mm above and 100 mm below. Use the smallest of the three.
Step 3: Take off the clearance
A shelf cut to the exact opening will not go in. Order 3 mm to 5 mm under the smallest figure, or give us the opening and say so.
Step 4: Decide the depth
Measure from the wall to where you want the front edge. Depth changes what the shelf holds, not how much it sags.
Step 5: Note how it is held
Brackets under the ends, a channel along the back or pins into the side walls. A shelf in channels at both ends is stiffer than one resting on two brackets.
Step 6: Choose the thickness
Use the span table below, then check the sag in the shelf load tool.
Which thickness do I need?
We cut shelves in 6 mm, 8 mm or 10 mm. As a guide, from our shelves and table tops page:
| Span between supports | Thickness |
|---|---|
| Up to 500 mm | 6 mm toughened |
| 500 to 800 mm | 8 mm toughened |
| Over 800 mm | 10 mm toughened, and check the sag |
A 6 mm shelf looks the same as a 10 mm shelf on a phone screen and sags far more over the same span. Do not choose it by eye.
Can a shelf have holes or shaped corners?
Yes. Holes are measured to their centre, X from the left edge and Y from the bottom edge, and drilled before toughening. Radius corners go from 5 mm to 200 mm in steps of 5 mm. A radius on the front corners is kinder to hips and hands in a narrow room. See holes, notches and cut-outs.
How accurate does it need to be?
We cut to plus or minus 2 mm. An alcove needs real clearance on top of that, which is why you order 3 mm to 5 mm under.
Where to go next
- Check the load: shelf load tool
- Order it: open the shelf configurator
- How to measure for a glass table top
Questions we get asked
Do I measure the alcove or the span?
Both. The alcove decides whether the shelf fits. The span between the supports decides the thickness.
How much smaller than the alcove should the shelf be?
3 mm to 5 mm under the smallest measurement, so it can be manoeuvred in.
Can I have a raked shelf?
Yes. Rake is offered on shelves, and a raked shelf is priced by hand for now.
Do you supply the brackets?
The configurator suggests shelf brackets for the shelf. You can also browse fixings in our shop.
Contact the team with your order reference and the step you need help with, or search all help topics.