Plasterboard is a sheet count: area divided by the area of one sheet, plus an allowance for cuts around doors, windows and corners.
Sheet sizes
The common sheet in both countries is 2400 × 1200 mm, which covers 2.88 m². British Gypsum also lists 1800 × 900 mm, which covers 1.62 m² and is easier to carry. Bunnings lists Gyprock at 2400, 2700 and 3000 mm long, all 1200 mm wide.
| Sheet | Area | Sheets per 10 m² |
|---|---|---|
| 1800 × 900 mm | 1.62 m² | 6.2 |
| 2400 × 1200 mm | 2.88 m² | 3.5 |
| 2700 × 1200 mm | 3.24 m² | 3.1 |
| 3000 × 1200 mm | 3.60 m² | 2.8 |
A worked wall
20 m² of wall with 10% for cuts is 22 m². In 2400 × 1200 mm sheets that is 7.6, so 8 sheets.
A single wall 3.6 m long and 2.4 m high is 8.64 m², which is three sheets stood on end with no cuts. Walls that match the sheet size waste very little; walls that do not can waste more than 10%.
Pick a sheet that fits the height
Sheets are usually fixed vertically, so a sheet as long as the wall is high avoids horizontal joints. In Australia, 2700 mm sheets suit 2.7 m ceilings.
What is left out
Screws, joint tape and compound are not counted. Fire, moisture and sound boards have their own rules for where they go; this page only counts sheets.
Figures are estimates for a shopping list. Check the pack or datasheet before you buy.