Common Glass Thicknesses for Residential Windows
Glass thickness affects strength, weight, acoustic performance, and cost. Choosing the right thickness for each application is both a compliance issue and a practical one. Here's a breakdown of the most common thicknesses used in residential glazing.
4mm Glass The lightest and thinnest commonly available option. Used for internal picture frames, cabinet glass, and small fixed panels in low-wind areas. Rarely used in exterior applications due to inadequate strength for wind loading. Weight: 10 kg/m².
6mm Glass The workhorse of residential glazing. Suitable for most standard windows, sliding doors, and fixed panels up to moderate sizes. When toughened, it meets AS 1288 safety glass requirements for most human impact zones. Weight: 15 kg/m².
8mm Glass Used for larger panels where 6mm doesn't meet wind loading requirements, or for frameless shower screens and internal partitions. As laminate (8.38mm), it's a common choice for balustrades. Weight: 20 kg/m².
10mm Glass Typically specified for large fixed panels, commercial shopfronts, and high-wind exposure applications. As toughened glass, it provides excellent strength for panels up to around 3m². Weight: 25 kg/m².
12mm Glass The standard for structural applications — frameless glass balustrades, large pivot doors, and commercial facades. Requires mechanical lifting for any panel over about 0.8m × 1.2m due to weight. Weight: 30 kg/m².
Laminated Configurations For laminated glass, the combined thickness is the sum of both panes plus the interlayer: • 6.38mm (3/0.38/3) — light, suitable for internal overhead glazing • 10.38mm (5/0.38/5) — balustrades, overhead glazing, skylights • 12.38mm (6/0.38/6) — structural balustrades, frameless glass
Double Glazed Units For IGUs, the specification format is glass/spacer/glass. Common residential configurations: • 4/12/4 — budget double glazing, older homes • 6/12/6 — standard residential, good thermal performance • 6/16/6 or 6/16/6 with Low-E — higher performance, recommended for new builds
Choosing the Right Thickness When in doubt: check AS 1288 tables for your panel size and wind zone, and always confirm with your glass supplier. If the application involves human impact risk, safety glass (toughened or laminated) is mandatory regardless of thickness.