Order the right amount, first time.
Calculators for UK DIY jobs and small builds. Type the measurements off your tape, in metres or feet and inches, and get an order list in bags, tonnes and panels.
Building materials calculators
See allHow much to order for slabs, paths, decks, fences, roofs, walls and floors, in the units merchants sell.
- Concrete calculatorSlabs, footings and post holes in m³ and bags
- Block paving calculatorBlocks, Type 1 and sand for a drive or patio
- Gravel calculatorTonnes and bulk bags for paths and drives
- Composite decking calculatorBoards, joists and clips for a deck
- Fence calculatorPanels, posts and postmix for a fence run
- Brick and block calculatorBricks or blocks and mortar for a wall
- Roof tile calculatorTiles and batten from roof area or plan and pitch
- Screed calculatorSand and cement for a floor screed
- Tile calculatorTiles, boxes and adhesive for walls and floors
- Plaster calculatorBags of finish plaster for a skim
- Wall panelling calculatorEven spacing for battens on a feature wall
Heating and energy calculators
See allRadiator sizes, appliance running costs and home EV charging at current UK prices.
Where the figures come from
Coverage and quantity figures come from manufacturers and merchants, such as Marshalls for paving depths, Tarmac for postmix and British Gypsum for plaster. Energy prices use Ofgem’s price cap for 1 October to 31 December 2026. Each calculator lists its sources and explains the sum, and how we calculate covers the assumptions. Figures were last checked on 25 October 2026.