LazyTools

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🧱 Drywall & Plasterboard Calculator

Enter the wall or ceiling area and your sheet size, add a waste allowance, and get the number of drywall sheets to buy.

Sheets to buy

3

incl. 12% waste

Before waste

1.9

32 sq ft/sheet

Joint compound (approx)

3 lb

Sheets = area ÷ sheet area, + waste (~10–15%). Compound estimate is approximate — check product coverage. 🔒 In your browser.

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How the drywall & plasterboard calculator works

The tool divides the total area by the area of one sheet, then adds a waste percentage for cuts and offcuts. A standard sheet is 4 × 8 ft (32 sq ft ≈ 2.97 m²), though 4 × 12 ft and 1.2 × 2.4 m sheets are also common — enter your sheet size.

Allow about 10–15% waste for cuts around doors, windows and corners. Buy a spare sheet or two — a single damaged board mid-job is annoying, and offcuts are handy for patches.

Frequently asked questions

How many sheets of drywall do I need?

Divide the wall and ceiling area by the area of one sheet, then add ~10–15% for waste. For 60 m² with 2.97 m² sheets: 60 ÷ 2.97 ≈ 21 sheets, plus waste ≈ 23–24.

What size is a standard drywall sheet?

In the US, 4 × 8 ft (32 sq ft); 4 × 12 ft is common for pros. In the UK/EU, plasterboard is often 1.2 × 2.4 m (2.88 m²). Enter your sheet size.

How much waste should I allow?

About 10% for simple rooms, up to 15% for rooms with many openings, angles or short walls where offcuts can’t be reused.

Do I count the ceiling?

Yes if you’re boarding it — add the ceiling area (length × width) to the wall area before dividing by the sheet size.

How much joint compound and tape do I need?

As a rough guide, about 0.5 kg of compound and 1 m of tape per m² of drywall, but this varies with the number of joints and coats.

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