Shower Glass Thickness: What You Need to Know

Shower glass comes in various thicknesses, each suited to different applications. According to the CPSC and industry standards, thickness affects safety, appearance, and installation requirements.

Common Thicknesses

According to FGIA, shower glass is typically available in:

| Thickness | Typical Use | Frame Requirement |
|-----------|-------------|-------------------|
| 1/8" (3mm) | Framed bypass doors | Full frame required |
| 3/16" (5mm) | Framed swing doors | Full frame required |
| 1/4" (6mm) | Semi-frameless | Partial frame |
| 3/8" (10mm) | Frameless standard | No frame needed |
| 1/2" (12mm) | Frameless premium/large | No frame needed |

Why Thickness Matters

According to ASTM testing and CPSC requirements:

Safety

• Thicker glass is stronger (more impact resistant)
• When tempered, thickness affects fragment size
• Frame provides support for thinner glass

Rigidity

• Thin glass flexes; thick glass is rigid
• Flex affects seal effectiveness
• Door movement feel differs by thickness

Weight

• 1/2" glass weighs nearly double 1/4" glass
• Heavier glass requires robust hardware
• Installation more demanding for thicker glass

Appearance

• Thicker glass has more prominent edge appearance
• Edge treatment (polished, beveled) more noticeable on thick glass
• Frameless look requires minimum thickness for safety

Frameless Requirements

According to FGIA, frameless doors require thicker glass because:

1. Glass must support itself structurally
2. Hardware attaches directly to glass
3. No frame compensates for flex or movement
4. Door weight must be carried by hinges/pivots

Minimum thickness for frameless:

• Small doors (under 18 sq ft): 3/8"
• Larger doors: 1/2" recommended
• Very large panels: May require 5/8"

Weight Comparison

According to FGIA specifications:

| Thickness | Weight per Sq Ft |
|-----------|------------------|
| 1/8" | 1.64 lbs |
| 3/16" | 2.45 lbs |
| 1/4" | 3.28 lbs |
| 3/8" | 4.91 lbs |
| 1/2" | 6.54 lbs |

A typical 3' × 6' frameless door panel (18 sq ft):

• At 3/8": ~88 lbs
• At 1/2": ~118 lbs

Cost Implications

According to industry pricing:

Thicker glass costs more due to:

• Higher material cost
• More expensive shipping/handling
• Specialized fabrication
• Heavier-duty hardware needed

Approximate price increase per step up in thickness: 15-25%

The Bottom Line

For framed doors, 1/8" to 3/16" is standard and appropriate. For frameless, according to CPSC and FGIA guidance, 3/8" is minimum with 1/2" preferred for larger panels. Don't skimp on thickness for frameless applications—it's a safety issue.

*For all glass options, see: [Shower Door Glass Options](/guides/shower-door-glass-options)*