Drywall Calculator
Calculate how many plasterboard sheets, screws, jointing compound and tape you need for any room or wall area. Works for walls and ceilings. Metric and imperial.
🔨 Drywall Calculator
📐 How It Works
Drywall quantity is the total wall and ceiling area divided by sheet area (2.88 m² for 2400×1200mm), with 10% waste added for cuts. Screws are estimated at 30–40 per sheet. Jointing compound and tape are estimated from total area.
📋 Worked Example
Bedroom 4m × 3.5m, 2.7m ceiling, walls + ceiling, 1 door, 1 window: Walls = 40.5−1.8−1.4 = 37.3 m². Ceiling = 14 m². Total = 51.3 m². Sheets = ceil(51.3×1.10÷2.88) = 20 sheets.
❓ Frequently Asked Questions
Standard walls: 10mm. Ceilings: 10mm (horizontal fix) or 13mm (better acoustic and fire performance). Wet areas: 10mm water-resistant (green board). Fire-rated walls: 13mm or 16mm as per specification. Always check the fire rating requirement for your application.
Approximately 30–40 screws per sheet for standard wall fixing at 300mm spacing on studs. Use 25mm coarse thread screws for 10mm board into timber, 35mm for 13mm board. Fix at maximum 300mm centres on studs and 200mm on edges.
Allow approximately 0.4–0.6 kg/m² of wall area for a 3-coat jointing system. A 20 kg bucket covers approximately 35–50 m². Buy slightly more than you think you need — runs and drips waste more than expected.
In climate zones with significant temperature extremes or in air-conditioned buildings, a vapour barrier (sarking or polyethylene film) behind the plasterboard is recommended. Check your local NCC requirements and the building designer's specification.