Tempered Glass Thickness Guide: 6mm, 8mm, 10mm & More
Choosing the correct tempered glass thickness is one of the most important decisions in any glass project. Whether you’re installing a shower enclosure, glass table top, balcony railing, or commercial partition, thickness directly affects strength, safety, performance, and longevity.
This comprehensive guide explains 6mm, 8mm, 10mm, 12mm, and thicker tempered glass options, where each thickness is best used, how load and safety factors work, and how to choose the right one for your application.
What Is Tempered Glass and Why Thickness Matters
Tempered glass—also known as toughened glass—is heat-treated safety glass that is 4 to 5 times stronger than ordinary annealed glass. The tempering process creates compressive stress on the surface, making it more resistant to impact and thermal shock.
However, thickness still plays a critical role:
- Thicker glass = higher load capacity
- Thicker glass = better rigidity and less flex
- Thicker glass = improved safety in structural applications
For many residential and commercial projects, builders choose tempered glass cut to size so thickness, dimensions, and edge finishes match exact requirements.
For a deeper understanding of safety glass behavior, the Glass Association of North America explains how thickness impacts strength and compliance:
👉 https://www.glass.org/glass-education/what-is-safety-glass
6mm Tempered Glass (¼ Inch): Lightweight & Practical
Best Uses
- Cabinet doors
- Interior partitions
- Small shelves
- Decorative panels
- Low-impact windows
Strength & Performance
6mm tempered glass is roughly 4x stronger than 6mm annealed glass, making it suitable for light-duty applications. However, it is not recommended for load-bearing or structural use.
Pros
✔ Lightweight
✔ Affordable
✔ Easy to install
✔ Clean, minimal appearance
Limitations
✘ Not ideal for large spans
✘ Can flex under pressure
✘ Limited impact resistance compared to thicker options
Typical applications: interior glazing where aesthetics matter more than structural strength.
8mm Tempered Glass (5/16 Inch): Balanced Strength
Best Uses
- Shower doors
- Medium glass shelves
- Table tops
- Office partitions
- Balustrade infill (non-structural)
Strength & Performance
8mm tempered glass offers noticeably improved rigidity over 6mm and is one of the most popular thicknesses for residential use.
It provides a good balance between strength, weight, and cost—especially in bathrooms and living spaces where safety matters.
Pros
✔ Good impact resistance
✔ Reduced flexing
✔ Suitable for frequent use areas
Limitations
✘ Not ideal for long unsupported spans
✘ May require framing for safety in tall installations
10mm Tempered Glass (⅜ Inch): Heavy-Duty Residential Favorite
Best Uses
- Frameless shower enclosures
- Glass railings (with support)
- Glass table tops
- Large shelves
- Glass doors
Strength & Performance
10mm tempered glass is significantly stiffer and more resistant to bending, making it ideal for frameless designs. It is often specified for safety-critical applications in homes.
In many projects, tempered glass panels of 10mm thickness are chosen because they meet common building safety requirements while maintaining a sleek appearance.
According to architectural glass guidelines from Pilkington, thicker safety glass improves both structural stability and user safety:
👉 https://www.pilkington.com/en/global/products/product-categories/architectural-glass
Pros
✔ Excellent rigidity
✔ Suitable for frameless installations
✔ Premium look and feel
Limitations
✘ Heavier
✘ Higher cost than thinner glass
12mm Tempered Glass (½ Inch): Structural & Commercial Grade
Best Uses
- Glass balustrades
- Stair railings
- Large glass doors
- Commercial partitions
- Outdoor glass barriers
Strength & Performance
12mm tempered glass is commonly used in structural and semi-structural applications. It provides high resistance to impact, wind loads, and human force.
In many cases, it is specified by building codes for areas where people may lean, push, or fall against glass.
The International Building Code (IBC) references safety glass requirements for guardrails and barriers:
👉 https://codes.iccsafe.org/content/IBC2021P2/chapter-24-glass-and-glazing
Pros
✔ High load capacity
✔ Minimal flex
✔ Suitable for safety barriers
Limitations
✘ Very heavy
✘ Requires professional installation
15mm–19mm Tempered Glass: Extra-Thick Specialty Applications
Best Uses
- Structural glass floors
- High-end commercial façades
- Public space railings
- Luxury furniture
- Heavy-duty tabletops
These thicknesses are less common in residential homes but are used where maximum strength and stiffness are required.
In many cases, designers combine thickness with lamination for additional redundancy and safety.
How to Choose the Right Thickness: Key Factors
1. Load & Usage
- Will people lean on it?
- Will it support weight?
- Is it subject to frequent impact?
2. Span Size
Larger glass panels require greater thickness to prevent flexing.
3. Safety Requirements
Areas like bathrooms, railings, and doors often require tempered glass sheets by building code.
4. Installation Type
- Frameless systems require thicker glass
- Framed systems can use thinner panels
5. Local Building Codes
Always confirm local regulations before selecting thickness.
For many home and commercial projects, using tempered glass ensures compliance with safety standards while offering durability and peace of mind.
Thickness Comparison Table
| Thickness | Common Use | Strength Level |
|---|---|---|
| 6mm | Cabinets, partitions | Light |
| 8mm | Showers, shelves | Medium |
| 10mm | Frameless doors, tables | High |
| 12mm | Railings, barriers | Very High |
| 15mm+ | Structural & commercial | Maximum |
Common Myths About Tempered Glass Thickness
❌ “Thicker glass is unbreakable”
Even thick tempered glass can break if edge damage occurs.
❌ “6mm tempered glass is unsafe”
6mm is safe when used correctly—just not for structural loads.
❌ “All applications need the thickest glass”
Over-specifying increases cost and weight without added benefit.
Final Thoughts: Choosing the Right Tempered Glass Thickness
There is no single “best” thickness—only the right thickness for the right application.
- Use 6mm–8mm for light interior applications
- Choose 10mm for frameless residential designs
- Select 12mm or thicker for railings and safety barriers
Understanding tempered glass thickness helps ensure safety, durability, compliance, and long-term performance—whether you’re designing a modern home or a commercial space.