Wood, stone and tile samples lined up on white shelves against a painted brick wall

Knowledge hub

Everything about calculating and planning a floor

Short, practical guides on the two questions every floor starts with: how much material do you need, and how do you get a laying plan you can actually build from?

Step by step on the floor

In the order of the real job: measure and plan first, then prepare the subfloor, lay the floor you chose, and finish with the joints and baseboards.

Measure and plan

Step 1Measure a room for flooringUse the floor plan as a start, take the numbers from the room: each wall in three places, both diagonals, alcoves, doors, pipes. With tolerances and tools.
2Step 2Make the layout planClick a room on your floor plan, adjust the corners, pick the material – and get your layout plan and material list. Free, no account, with video.
Starting from a drawing, a building model or a scan you already have:
Decided in the layout plan:
- Choose the laying direction

Before laying: material and subfloor

Step 3Prepare a subfloorScreed moisture limits, how to measure flatness, which old floors can stay, how much self-leveling underlayment per m² – with sources.
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Step 4 – floating floors only
On screed, concrete or old tiles a vapor barrier goes under the underlayment, and many underlayments have it built in. Never on a wooden subfloor; glued floors and tiles need neither.
- Lay a vapor barrier
- Install floor underlayment

Lay the floor

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Step 5 – pick the one for your floor

Finish: joints and baseboards

Step 6 – tiles onlyGrout floor tilesGrout floor tiles properly: when the adhesive is dry enough, which grout suits which joint, how many kilograms per m² you need and why grout dries patchy.
Step 7Install baseboardsInstall baseboards properly: expansion gap, fastening for your wall, clip and nail spacing, corners cut to the real angle, door frames, caulk on top only.

Step 4 – Photo: marsupium photography, CC BY-SA 2.0, cropped, via Wikimedia Commons

Step 5 – Photo: Raphael Mecke, CC BY 4.0, via Wikimedia Commons

Background: where the numbers come from

Articles rather than calculators: why a laid-out plan orders differently from a flat waste allowance, how the laying pattern changes the waste, and finished example rooms with their counts.

Exact versus rule of thumbWhy a laid-out plan orders differently from a flat waste allowance, with a worked example.
Pattern calculatorHow the laying pattern changes the waste: straight, offset, herringbone and chevron compared.
Herringbone waste %Why herringbone takes more material than a straight lay, and where the extra goes.
Example floor plansFinished example rooms with their piece counts, cut pieces and packs, ready to open in the planner.

Calculators: how much material do you need?

Each of these returns a number. Primer, screed, self-leveling underlayment, tile adhesive and grout are worked out from the area, the layer or joint size and the maker's consumption rate; tiles and laminate are counted piece by piece in the planner from the room you draw; slabs and pedestals for a raised terrace are counted on the page itself.

Primer calculatorPrimer in liters for your area and the absorbency of the subfloor.
Screed calculatorBags of screed from the area and the layer thickness.
Self-leveling underlayment calculatorBags of self-leveling underlayment from the area and the average layer thickness.
Tile calculatorTiles, cut tiles and packs, counted in the planner from the room you draw.
Tile adhesive calculatorBags of tile adhesive from the area and the notched trowel you use.
Grout calculatorBags of grout from the tile size, the joint width and the joint depth.
Laminate calculatorPlanks, cut pieces and packs, counted in the planner from the room you draw.
Patio slab calculatorSlabs and pedestals for a raised terrace: middle, edge and corner pedestals, height ranges and packs.

Screed calculator – Photo: Frank Eritt, CC BY-SA 4.0, via Wikimedia Commons

Self-leveling underlayment calculator – Photo: Wonderlane, CC BY 2.0, cropped, via Wikimedia Commons

Rather see it than read it?

Load a demo floor plan, pick a material and let the planner lay every plank. The guides make a lot more sense with a finished plan in front of you.

Start planning