Plasterboard Quantity Calculator
Sheets, screws and joint tape from area, sheet size and layers.
Inputs
Result
Formula
| Area | A = length × height |
| Per sheet | a = length × width ÷ 10⁶ |
| Sheets | n = ceil(A × layers × (1 + waste) ÷ a) |
| Screws | N = board area × 25 |
| Tape | L = board area × 1.6 |
An 18 m² wall in 2400 × 1200 sheets, single layer, 8% waste: 7 sheets, about 525 screws, 32.3 m of tape and 8.1 kg of compound.
FAQ
Why 8% waste?
A sheet is 2.88 m² and offcuts are rarely reusable. A 3 m wall with 2.4 m sheets needs a 0.6 m strip per column cut from another sheet, of which 1.8 m is only just usable. Add openings, corners and services and 8% is conservative; walls with many penetrations need 10-15%.
Why must joints be staggered?
Four sheet corners meeting produce a cross joint, the point most likely to crack. Joints on adjacent sheets must be offset by at least 400 mm and never form a cross. At openings, cut an L-shaped sheet from a single board rather than building the corner from two pieces.
Single versus double layer?
A second layer adds 3-5 dB of sound insulation and roughly doubles fire resistance, but nearly doubles material and labour and adds 12 mm to thickness, affecting door linings and clear dimensions. Single layer suits most partitions; plant rooms, home cinemas and quiet bedrooms warrant two layers with staggered joints.
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Results are estimating aids only and are not a design basis. Construction and final accounts must follow the drawings, the applicable standards and an approved method statement. Anything affecting structural safety, shoring or falsework must be checked by a suitably qualified engineer.