Square metre calculator
Calculate the area of a rectangular room.
Open calculatorCleverCalc · Guides
Plan laminate and paint: floor area, waste and coats
Plan materials for a room in the right order. Floor area and wall area are different quantities. Calculate them separately, choose an appropriate allowance and round up when buying full packs or paint containers.
The right calculatorsHow to get started
- 01
Measure length and width in the same unit. Split irregular rooms into rectangles and add their areas. Walls also need height; subtract openings that will not be painted consistently.
- 02
Choose waste allowance for the laying pattern, room shape and manufacturer’s guidance. A 10% example is not a universal rule. Divide the required area by coverage per pack afterwards.
- 03
For paint: litres = wall area × coats ÷ coverage in m²/L per coat. Check the surface, primer and manufacturer’s rating. Then compare whole containers and allow a justified reserve.
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Laminate flooring calculator
Calculate laminate flooring including waste and pack size.
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Calculate wall area of a rectangular room minus openings.
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Calculate litres of paint needed for a wall area.
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Calculate tile quantity including waste.
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Calculate wallpaper rolls including waste.
Open calculatorA worked example
Plan laminate and paint: floor area, waste and coats
A 4.5 × 3.2 m floor is 14.4 m². An illustrative 10% waste allowance gives 15.84 m². At 2.2 m² per pack: 15.84 ÷ 2.2 = 7.2, so buy 8 packs covering 17.6 m². For 85 m² of walls, two coats and 8 m²/L coverage, the estimate is 21.25 L before any extra reserve. Do not substitute floor area for wall area.
Frequently asked questions
When should I round up?
Calculate measured areas and the chosen allowance first. Round up the number of complete packs or containers at the end. Rounding every intermediate step heavily can lead to unnecessary surplus.
Does one coverage figure work for every wall?
No. Absorbency, texture, colour changes and application affect usage. The manufacturer’s figure is a starting point; inspect the surface and consider a test coat. A calculator cannot replace an on-site material check.
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