Determine the glass thickness of your shower

Why glass thickness is decisive

The right shower seal is a question of glass thickness. A 6 mm seal won't fit on 8 mm glass — it sits too loose, water leaks through. An 8 mm seal on 6 mm glass goes on, but it bulges and looks ugly.

Four glass thicknesses are common in German-speaking and most European markets:

| Glass thickness | Typical use | |---|---| | 6 mm | DIY-store standard, smaller shower enclosures | | 8 mm | Premium segment, modern walk-ins | | 10 mm | Architect walk-ins, large glass surfaces | | 12 mm | Rare, custom-builds, partition walls |

Method 1: calliper (precise)

If you have a calliper to hand, it's the most reliable method.

1. Open the calliper.
2. Place the jaws on the glass edge — one jaw on the outside, one on the inside.
3. Close until both jaws touch the glass.
4. Read the value. Glass thickness is usually displayed to 0.1 mm.

For 6 mm you might read e.g. 5.9 or 6.1 mm — that's tolerance, not error. A 6 mm seal fits 5.8–6.3 mm.

Method 2: glass thickness gauge (very precise)

Building-trade suppliers sell glass thickness gauges — small plastic cards with cutouts for the standard sizes. If a cutout has play, the glass is thinner; if it sits firmly, it is exactly that thickness.

A cheap gauge costs €5–10. If you want certainty, this is the easiest solution.

Method 3: ruler & common sense

If you have neither calliper nor gauge, this works too:

1. Hold a ruler with millimetre scale against the glass edge.
2. Use a magnifying glass or smartphone camera to enlarge the glass.
3. Read.

It's not millimetre-precise — but between 6 and 8 mm you'll clearly see the difference.

Method 4: smartphone trick

Modern smartphones have good cameras. You can:

1. Place a ruler directly against the glass edge.
2. Take a sharp photo with the smartphone from 5–10 cm distance.
3. Zoom into the photo at 200–300 % and read the thickness.

Works surprisingly well and is contact-free.

Method 5: manual estimate (last resort)

If nothing of the above is to hand:

• Pressure-point test: press lightly with your thumbnail on the glass edge. 6 mm glass is noticeably "thinner" — you feel that your thumb tip almost protrudes over the glass edge. With 8 mm the thumb sits clearly supported.
• Visual comparison: hold a folding ruler next to it. In good light, 6 vs. 8 mm is clearly distinguishable.

But: this is an emergency solution. With tight tolerances (e.g. between 6 and 8 mm), buy a glass thickness gauge.

Where is "the glass edge"?

Important: you measure the full glass thickness on a non-clamped edge.

• Not through a profile rail — you'd measure two layers.
• Not at a drilled hole — holes are often tapered.
• Ideally at the front door edge or the free glass edge of a walk-in.

What to do if you're between sizes?

Sometimes glass thickness is between the standard values — e.g. 7 mm or 9 mm.

• 7 mm glass: go for a 6 mm seal with wide tolerance (often labelled "for 6–8 mm"). It will sit a bit tighter, which is fine.
• 9 mm glass: choose an 8 mm seal with "8–10 mm" tolerance.
• 5 mm glass: very rare. Order custom sizes directly from the manufacturer if needed.

Special case: different glass thicknesses in one shower

Some manufacturers use different glass thicknesses — e.g. 8 mm on the door and 10 mm on the fixed panel. So measure each glass surface separately wherever a seal sits.

The configurator currently has only one "glass thickness" field — if you have different thicknesses, run a separate configuration per glass.

Summary

1. Calliper or glass thickness gauge are the most reliable tools.
2. Smartphone + ruler is a good emergency solution.
3. Standard is 6 or 8 mm — other thicknesses are rarer.
4. When in doubt: buy a seal with a slightly wider tolerance range.

→ Glass thickness measured? Launch the configurator now.