By Zencalcy Editorial TeamLast reviewed About us
Glass weighs about 2.5 g/cm³, which works out to 1.6 lb per square foot for every 1/8 inch of thickness. That makes the arithmetic memorable: a ¼-inch pane is about 3.3 lb/ft², and a ½-inch pane about 6.5 lb/ft². This calculator handles float, tempered and laminated glass at any size.
Weight per square foot for glass by thickness.
Weight = A × t × 2,500 kg/m³
A is area and t is thickness, both in metres. Laminated glass adds a PVB interlayer of about 1,070 kg/m³, so a 6 mm/6 mm laminate is roughly 3% heavier than solid glass of the same total thickness. Tempering does not change density.
| Symbol | Meaning |
|---|---|
| A | Area of the pane. |
| t | Glass thickness. |
| ρ | Density, about 2,500 kg/m³. |
The pane is 6 sq ft, and ¼-inch glass weighs about 3.28 lb/ft², so the pane weighs roughly 19.7 lb (8.9 kg).
Continue with the Gravel Calculator, Sand Calculator, Rock Calculator, or the River Rock Calculator — or browse more materials & quantities and all construction calculators.
About 1.64 lb. Add 1.64 lb/ft² for each additional 1/8 inch.
Results use standard construction estimating arithmetic: volumes from measured area and depth, unit weights from published material densities, and code-referenced spans or clearances where the page names a code. Quantities are rounded up to whole saleable units and include the stated waste allowance. These tools are planning aids, not structural design, and do not replace a licensed engineer, a local code check, or a contractor's site measurement.
Reference material used to build and check this calculator:
Last reviewed: September 2026. See how we build and check every tool on the about page.
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Content updated: September 2026