BuildCalcs Free UK building calculators.
Calculate with confidence.
Clear, practical construction calculators for concrete, brickwork, roofing, flooring, landscaping, decorating and more — built around UK metric measurements.
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Jump straight to a common calculation, or browse the complete directory below.
Concrete
Slabs, bases, footings and post holes.
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Brickwork
Bricks per m², wall quantities and waste.
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Roof tiles & slates
Estimate roof covering quantities and waste.
Calculate coverings →
Flooring
Floor area, packs, tiles and screed.
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Landscaping
Paving, gravel, decking and soil.
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Decorating
Paint and wallpaper planning.
Open calculator →From measurements to a planning quantity
BuildCalcs keeps the process deliberately simple, while showing the assumptions that matter.
Building & DIY calculators
Search all 23 tools or filter by project type.
Plasterboard Calculator
Calculate sheet quantities from wall dimensions, board size and waste allowance.
Calculate plasterboardStud Wall Calculator
Estimate vertical stud count and approximate timber length for a partition wall.
Calculate studsPaint Calculator
Estimate litres of paint for a room using wall size, coats and paint coverage.
Calculate paintConcrete Calculator
Calculate m³ and litres for slabs, bases, footings and post holes, with bag-yield and ready-mix estimates.
Calculate concreteBrick Calculator
Calculate bricks per m², openings, waste, packs and estimated brick cost.
Calculate bricksInsulation Calculator
Estimate insulation area and the number of packs required from product coverage.
Calculate insulationFlooring Calculator
Work out room area and packs of laminate or other packaged flooring.
Calculate flooringTile Calculator
Estimate wall or floor tile quantities from surface and tile dimensions.
Calculate tilesMortar Calculator
Estimate cement and sand quantities for a target mortar volume and mix ratio.
Calculate mortarGravel Calculator
Convert area and depth into cubic metres and approximate tonnes of aggregate.
Calculate gravelPaving Slab Calculator
Estimate how many slabs are needed for a rectangular patio or path.
Calculate pavingDecking Calculator
Estimate linear metres and full board quantities from deck dimensions.
Calculate deckingRoof Tile & Slate Calculator
Estimate roof tile or slate quantities from slope area, units per square metre and waste.
Calculate tiles or slatesScreed Calculator
Calculate floor screed volume and approximate premixed bag quantities.
Calculate screedRoof Pitch Calculator
Convert roof rise and run into pitch angle, slope factor and rafter length.
Calculate roof pitchSand Calculator
Estimate sand volume, tonnes, bulk bags and 25kg bags for your project.
Calculate sandMOT Type 1 / Hardcore
Estimate sub-base volume, tonnes and bulk bags from area and compacted depth.
Calculate Type 1Wallpaper Calculator
Calculate rolls from wall size, roll dimensions and pattern repeat.
Calculate wallpaperRender Calculator
Estimate render wall area, wet volume, material weight and bag quantity.
Calculate renderSquare Metre Calculator
Calculate m² and square feet with an optional material allowance.
Calculate m²Rafter Length Calculator
Estimate common-rafter length from span, roof angle and eaves overhang.
Calculate raftersTry a broader search term or choose another category.
Popular project calculators
Common starting points for building and home-improvement projects.
Useful numbers, with the limits made clear
These calculators are intended for early-stage planning. Material yields, coverage, product dimensions and project conditions can vary, so relevant calculators let you adjust key assumptions rather than hiding them.
Check product informationManufacturer and supplier data should override generic planning values.
Use actual site dimensionsReal measurements are more useful than nominal sizes wherever possible.
Professional requirements still applyQuantity estimates do not replace structural, safety or regulatory advice.
Learn before you order
Building & estimating guides
Go beyond the result. Our guides show the formulas, worked examples, reference tables and assumptions behind common building quantities.