How Many Plasterboard Sheets for a Room?

How We Calculated This

For a standard UK room measuring 3.5m x 4m with 2.4m high ceilings:

• Two walls at 3.5m wide: 2 x 3.5m x 2.4m = 16.8m²
• Two walls at 4m wide: 2 x 4m x 2.4m = 19.2m²
• Total wall area: 36m²

Sheet Size and Coverage

The most common plasterboard size in the UK is 2400mm x 1200mm, which gives a coverage of 2.88m² per sheet. Standard thickness is 12.5mm for walls.

• Sheets needed (no wastage): 36 ÷ 2.88 = 12.5 sheets
• With 10% wastage: 12.5 x 1.10 = 13.75, rounded to 14 sheets

In practice, 13 sheets is usually enough for this size room because you can reuse offcuts from one wall on the next. Buy 14 if you want a comfortable margin.

Common UK Plasterboard Sizes

• 2400 x 1200mm (8’ x 4’): Most common for walls — 2.88m² per sheet
• 2400 x 900mm: Easier to handle solo — 2.16m² per sheet
• 3000 x 1200mm (10’ x 4’): For higher ceilings — 3.6m² per sheet
• 1800 x 900mm (6’ x 3’): For small areas and patches — 1.62m² per sheet

What About the Ceiling?

If you also need to board the ceiling, add the floor area: 3.5m x 4m = 14m². That is an extra 5–6 sheets of 2400 x 1200mm board (with wastage), bringing the total to around 19 sheets.

Fixings You Will Need

You will need approximately 32 drywall screws per sheet when fixing to timber studs at 150mm centres around edges and 300mm centres in the field. For 13 sheets, that is roughly 400–420 screws. Buy a box of 500 to be safe.

If you are dot-and-dabbing to a solid wall, you will need approximately 0.5kg of adhesive per m², so around 18kg total — one 25kg bag of Gyproc Dri-Wall adhesive will cover this room.

Tips

Always use the longest board that fits the wall height to minimise horizontal joints. For 2.4m ceilings, 2400mm boards fit perfectly floor-to-ceiling with no cross joints. Stagger vertical joints between rows and do not line them up with door or window edges, as this causes cracking.