Glass · Doors
Glass door weight calculator
A glass door of 900 × 2100 mm weighs 47.3 kg (104.2 lb) in 10 mm glass, 56.7 kg in 12 mm and 37.8 kg in 8 mm. Glass is 2.5 kg per square metre for every millimetre of thickness. The page also works out what that weight does to the fitting: a door on hinges or pivots tries to turn out of its opening, and the top support is pulled out with a force that grows with the width; a sliding door shares its weight between two rollers.
How it is worked out
Glass weighs 2500 kg/m³ (EN 572-1). For the door above in 10 mm: 0.9 × 2.1 × 10 × 2.5 = 47.3 kg. A door that turns about a vertical axis holds its weight at its centre, half its width b from the edge; the axis is a from that edge (nothing, for hinges on the edge; 50 to 70 mm, typically, for a pivot), so the weight turns the door about the axis with an arm of b/2 − a. The two supports, d apart, resist with equal and opposite horizontal forces: the top one pulled out of the frame, the bottom one pushed into it. On hinges 1700 mm apart, the 10 mm door pulls the top hinge with 12.5 kg; on pivots 60 mm in and 2100 mm apart, with 8.8 kg. The vertical load, the whole weight, goes to the bottom pivot or floor spring, or is shared by the hinges as the maker's rating assumes.
Weight of a glass door by thickness
| Thickness | kg/m² | 800 × 2000 | 900 × 2100 | 1000 × 2200 |
|---|---|---|---|---|
| 6 mm | 15.0 | 24.0 | 28.4 | 33.0 |
| 8 mm | 20.0 | 32.0 | 37.8 | 44.0 |
| 10 mm | 25.0 | 40.0 | 47.3 | 55.0 |
| 12 mm | 30.0 | 48.0 | 56.7 | 66.0 |
| 15 mm | 37.5 | 60.0 | 70.9 | 82.5 |
| 19 mm | 47.5 | 76.0 | 89.8 | 104.5 |
Door weights in kg. For pounds, multiply by 2.2. Holes, notches and patches change the weight by a few per cent at most.
What this page does not do
- It does not rate the fitting. The capacity and the maximum width are the ones you type from the datasheet; many fittings give a maximum height too.
- It does not check the glass. A door is safety glass, toughened or laminated, and its thickness follows the fitting maker's table.
- It does not check the frame or the floor. The pull lands on the frame's fixings; a floor spring needs the screed for its box.
Questions people ask
- How much does a glass door weigh?
- A door of 900 × 2100 mm weighs 37.8 kg in 8 mm glass, 47.3 kg in 10 mm and 56.7 kg in 12 mm: width × height in metres × thickness in mm × 2.5.
- How much does a 12mm glass door weigh?
- 12 mm glass weighs 30 kg per square metre, so a 900 × 2100 mm door weighs 56.7 kg (125.0 lb).
- How much does a sliding glass door weigh?
- The same as any pane of its size and thickness: a 10 mm panel of 900 × 2100 mm is 47.3 kg, and each of its two rollers carries half, 23.6 kg.
- Why does the width of a glass door matter for the hinges?
- The door's weight acts at its centre, half its width from the hinges, and tries to turn it out of the opening. The top hinge holds it with a force of weight × half the width ÷ the distance between hinges: a wider door pulls harder.