Glass thickness is the first real decision in any frameless shower project — and the one that quietly drives everything downstream: door weight, which shower hinges you can use, panel stability, shipping cost, and even compliance. This guide compares the three specification grades — 8mm, 10mm, and 12mm tempered glass — so you can specify with confidence instead of guessing.
1. Why thickness is the first decision
All shower glass must be tempered (toughened) safety glass — it shatters into small dull cubes rather than sharp shards. Within that rule, thickness is what matters:
- Weight: glass is 2.5 kg/mm(All weights listed below are theoretical weights) of thickness per square metre. An 8mm sheet is 20 kg/m²; 12mm is 30 kg/m². That weight lands on your hinges.
- Rigidity: thicker glass flexes less, feels more solid, and reads as more "premium".
- Hinge rating: every hinge is engineered for a glass range (e.g. 8–10mm). Mismatch the range and the door won't seat correctly.
- Cost: thicker glass costs more in material, crating, and freight — and is harder to handle on site.
2. 8mm tempered glass — light and economical
At 20 kg/m², 8mm is the lightest frameless option. It suits:
- Small fixed screens and panels up to roughly 900mm wide
- Light swing doors under 25kg total
- Budget or space-constrained residential bathrooms
Use light-duty hinges rated for 6–8mm glass. Avoid 8mm for tall, full-height doors — it flexes noticeably and can feel less substantial.
3. 10mm tempered glass — the industry standard
10mm (25 kg/m²) is the most common frameless specification worldwide, and for good reason: it balances rigidity, weight, and cost. It handles:
- Standard swing doors 700–1000mm wide
- Heights up to 2000mm
- Most residential and light-commercial enclosures
Pair it with standard 8–10mm or 8–12mm hinges. If you only remember one number from this article, remember 10mm — it's the safe default for 90% of frameless showers.
4. 12mm tempered glass — heavy and premium
12mm (30 kg/m²) is the luxury/commercial grade. It's the right call when:
- Doors exceed 1000mm wide or carry double panels
- The project is hotel, commercial, or high-end residential
- You want maximum rigidity, acoustic mass, and a substantial feel
Specify heavy-duty hinges rated for 10–12mm glass with a higher load rating. Budget for increased crating and freight — 12mm is noticeably more expensive to ship.
5. Match the glass to the hinge
Thickness and hinge are a pair, not separate choices. Confirm the hinge's stated glass range covers your spec, then verify the rated load of the hinge pair exceeds the total door weight with margin. Our shower hinge buyer's guide walks through this in detail, and you can browse the full glass hinge range by category.
6. Building codes & regional notes
Tempered safety glass is mandatory for showers in every major market, but minimum expectations differ. Always confirm the local code with the project's certifier — coastal or public/commercial jobs often demand thicker glass or specific ratings.
7. Common mistakes to avoid
- Mixing thicknesses without re-matching hinges — a hinge rated 8–10mm will not seat 12mm glass.
- Under-specifying large doors — a 1100mm door on 8mm glass will flex and stress the hardware.
- Forgetting weight in logistics — 12mm panels need stronger crating and more careful handling.
PAIHUI HARDWARE is an ISO 9001-certified manufacturer of frameless shower door hardware, exporting to 50+ countries. Explore the full catalog at paihuihardware.com/products.
Not sure which thickness your project needs?
Send us your door width, height, and opening type — we'll specify the glass thickness and a matched hinge set with load data.
Get a Quote →Frequently Asked Questions
What thickness tempered glass should I use for a frameless shower?
For most residential frameless showers, 10mm (3/8") tempered glass is the standard and safest default. Smaller fixed screens can use 8mm, while large or commercial doors wider than 1000mm typically need 12mm for rigidity and to spread the door weight across the hinges.
Is 8mm glass strong enough for a shower door?
8mm tempered glass is safe and code-compliant for smaller doors and fixed panels up to about 900mm wide and under ~25kg total. For full-height or wider swing doors, 10mm or 12mm is recommended to avoid visible flex and long-term hinge stress.
Does glass thickness change which hinge I need?
Yes. Every hinge is engineered for a specific glass range (for example 8–10mm or 10–12mm). The hinge's rated range must cover your glass thickness, otherwise the door will not seat correctly and may crack at the drill point. Browse the full glass hinge range by specification.
How much does shower glass weigh per m²?
Tempered glass is roughly 2.5 kg per mm of thickness per square metre: about 20 kg/m² at 8mm, 25 kg/m² at 10mm, and 30 kg/m² at 12mm. This weight is what your hinges must support, so it drives the load rating you specify.