Shower glass thickness explained: 6mm, 8mm or 10mm?

Thickness is one of the first numbers you see on a shower screen listing, and it is easy to assume thicker is always better. It is not that simple. The right thickness depends on how the glass is supported, how big the panel is and what your walls can carry.

First, the safety basics

Shower glass should always be toughened safety glass. Toughening heats and rapidly cools the glass so it is several times stronger than ordinary glass of the same thickness. If it does break, it shatters into small blunt pieces rather than long sharp shards.

Look for glass marked to BS EN 12150, the standard for thermally toughened safety glass. The mark is usually etched discreetly in one corner. Thickness does not replace toughening: a thick panel of untoughened glass is not a safe shower screen.

What each thickness is typically used for

4mm to 6mm

Common in framed enclosures, sliding doors, bath screens and budget quadrant enclosures. The frame supports the glass, so it does not need to be heavy. Expect some flex if you push on a large panel.

8mm

The most common thickness for walk-in panels and many semi-frameless doors. It feels noticeably more solid than 6mm and is stiff enough to stand with a wall channel and a single support bar for typical panel sizes.

10mm

The usual standard for frameless hinged doors and larger fixed panels. It flexes very little, feels substantial when you open the door and gives the clean, heavy look many people want from frameless glass.

12mm

Used for very large or very tall panels, or high-end installations where minimal hardware is the goal. It is heavy, so walls, hinges and handling all need extra thought.

Weight adds up quickly

Glass weighs roughly 2.5kg per square metre for every millimetre of thickness. That gives a useful rule of thumb:

A 1m by 2m walk-in panel in 10mm glass weighs around 50kg. That is why wall construction, fixings and safe handling matter so much with thicker glass. It is also why many frameless installs need two people.

Does thicker glass leak less?

Not on its own. Water containment depends mainly on the design (door style, seals, drip bars, tray or floor gradient) and on where the shower head points. A well designed 8mm walk-in with the right panel length can keep water in better than a poorly planned 10mm door.

Does thicker glass cost more?

Yes. Thicker glass costs more to make and toughen, weighs more to deliver and needs stronger hardware. The difference between 8mm and 10mm is usually noticeable on the final price, especially for made-to-measure panels. See our cost guide for rough ranges.

How to choose

1. Start with the support method. Framed: 6mm is normal. Wall channel and support bar: 8mm or 10mm. Hinged frameless door: 10mm is the usual choice.
2. Check panel size. Larger and taller panels generally need thicker glass to stay stiff.
3. Check your walls. Heavier glass needs solid masonry or properly reinforced stud walls.
4. Follow the manufacturer. The hinge or channel manufacturer will state the glass thickness and maximum panel weight their hardware is designed for. Stay within it.

Quick checklist before you buy

• Is the glass toughened and marked to BS EN 12150?
• Does the thickness match the hardware rating?
• Can your wall take the weight?
• Is there an easy-clean coating, and on which side?
• What warranty covers the glass and the fittings?

Comparing styles as well? Read frameless vs framed shower screens.