Solve backwards
How big a ceiling will my plasterboard sheets cover?
- 8 sheetsThe example worked below
- Ceiling Plasterboard (Gypsum Board) Sheet CalculatorEvery figure is its own
You have
How much ceiling plasterboard?
Worked by the Ceiling Plasterboard (Gypsum Board) Sheet Calculator at the settings below.
The settings it uses
- Sheet Area
- 32 sq ft
- Waste Allowance (%)
- 10
What it will do
233 sq ft of ceiling
21.6 m²
One room. Enough for a room about 15.3 × 15.3 ft.
Or several. About 1 room of the size the Ceiling Plasterboard (Gypsum Board) Sheet Calculator opens on: a room about 14.8 × 14.8 ft.
Check it forwards
- Ceiling Area
- 233 sq ft
- It asks for
- 8 sheets
- You have
- 8 sheets
The Ceiling Plasterboard (Gypsum Board) Sheet Calculator asks for 8 sheets at that size, and 9 sheets one step larger.
If you had more, or less
Around your amount
Each worked by the Ceiling Plasterboard (Gypsum Board) Sheet Calculator at the same settings.
Half
4 sheets
116 sq ft
a room about 10.8 × 10.8 ft
Yours
8 sheets
233 sq ft
a room about 15.3 × 15.3 ft
Half as much again
12 sheets
349 sq ft
a room about 18.7 × 18.7 ft
Double
16 sheets
465 sq ft
a room about 21.6 × 21.6 ft
Common amounts
What each amount of ceiling plasterboard covers
The sizes it is usually sold in, each worked by the Ceiling Plasterboard (Gypsum Board) Sheet Calculator at the settings above.
| You have | It covers | As one room | Average rooms |
|---|---|---|---|
| 4 sheets | 116 sq ft(10.8 m²) | a room about 10.8 × 10.8 ft | under 1 |
| 8 sheets | 233 sq ft(21.6 m²) | a room about 15.3 × 15.3 ft | 1 |
| 12 sheets | 349 sq ft(32.4 m²) | a room about 18.7 × 18.7 ft | 1 |
| 20 sheets | 582 sq ft(54.1 m²) | a room about 24.1 × 24.1 ft | 2 |
The market's sheet, overhead
A 4 by 8 foot sheet covers 32 square feet, 2.97 m², in North America, and a 1200 by 2400 mm sheet 2.88 m², 31 square feet, elsewhere — the page counts the one your market sells. Ten per cent is carried for the cuts around fixtures, edges and openings that ceilings need more of than walls, and read backwards it comes off.
The longest board that fits
A butt joint has no tapered edge to bury the tape in, and on a ceiling every one shows under light raking from a window. So a ceiling is best hung with the longest board that will get into the room — eight and twelve foot sheets can give the same count here and a very different ceiling to finish.
Board that will not sag
Ordinary ½ inch (12.5 mm) board on ceiling framing at 24 inch (600 mm) centres is marginal, which is why ⅝ inch (15 mm) and sag-resistant grades exist; a water-based texture or blown insulation on top of the wrong one sags between the joists within a season. The count is the same; the board is not.
How the answer is worked
Nothing here is a second formula. The Ceiling Plasterboard (Gypsum Board) Sheet Calculator runs forwards — a size in, a quantity out — and this page grows its own starting room in proportion until the quantity it asks for is what you have. Where it rounds up to whole containers, the answer is the largest size before the next one would be needed.
Where the calculator adds an allowance for cuts or breakage when you order, the same allowance comes off here, because it is the same calculator: a stack you already own finishes less than its face value. Where it adds none, neither does this page — the settings beside the answer say which.
Ceiling Plasterboard (Gypsum Board) Sheet Calculator
runs it forwardsCalculate how many gypsum board sheets are needed to fasten directly to a ceiling's framing, with waste allowance.
Work out what to buy insteadSolve backwards
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Solve backwards
Start from what is already in the yard
Paint, sheets, rolls, bags and pieces, each read the other way by the calculator that orders it.
The calculator's own figures
Nothing is estimated twice: the page runs the same calculator you would order with.
The largest size that fits
Where a calculator rounds up to whole containers, the answer stops before the next one.
Both unit systems
Gallons and litres, square feet and square metres, side by side.
Frequently asked questions
- How much ceiling does 8 sheets of ceiling plasterboard cover?
- At the Ceiling Plasterboard (Gypsum Board) Sheet Calculator's own settings, 233 sq ft (21.6 m²) — a room about 15.3 × 15.3 ft. That is about 1 room of the size the calculator opens on: a room about 14.8 × 14.8 ft. Every figure follows the settings, which you can change in the calculator.
- How many sheets of drywall do I need for a 12 by 12 ceiling?
- A 12 by 12 foot ceiling is 144 square feet (13.4 m²), which is 4.5 sheets of 4 by 8 before cuts; with ten per cent for fixtures and edges, about 5 sheets. In practice, 12 foot sheets across the joists make fewer butt joints — three would board it.
- What thickness drywall should I use on a ceiling?
- Ceilings framed at 16 inch (400 mm) centres commonly take ½ inch (12.5 mm) board; at 24 inch (600 mm) centres, or with insulation or texture above, use ⅝ inch (15 mm) or a sag-resistant ceiling board. The local code and the board maker's span tables decide.
- Why does ceiling drywall need more waste than walls?
- Because light fittings, vents, access panels and the cuts at every edge land in full sheets overhead, where offcuts are hard to reuse. Ten per cent is a common allowance for a plain ceiling; a ceiling crowded with fittings, or a tray or coffered design, needs more.