Show the formula and working
This flooring cost calculator works out the full price of a new floor for homeowners and renters in the UK and Europe: the flooring itself, underlay, fitting and the small extras that are easy to forget. Enter the room size, the pack coverage and your prices, and it shows the packs to buy, a cost breakdown and an all in price per square metre, with a pound and euro switch and a feet and inches option.
Quick answer: Multiply the room area by 1.1 for 10% wastage, round up to whole packs, then multiply by the price per m². Add underlay, fitting and extras. A 4 m by 3.5 m room with £25 flooring, £4 underlay, £15 fitting and £40 extras costs about £711.60. The flooring cost calculator shows each part.
What Is a Flooring Cost Calculator?
A flooring cost calculator is a tool that turns a room’s size and your quoted prices into a total budget for laying a new floor. The formula in plain words: area = length x width; flooring to buy = area plus a wastage allowance, rounded up to whole packs; flooring cost = square metres bought x price per m². Underlay, the cushioning layer described in Wikipedia’s underlay article, is priced on the area with wastage, fitting is priced on the room area, and a lump sum covers trims, door bars, beading and delivery.
Because packs only come in whole numbers, you usually pay for a little more flooring than the room needs. The calculator shows that difference so the price matches what you will actually be charged at the till.
How Do You Use the Flooring Cost Calculator?
- Enter the Room length and Room width. For an L shaped room, split it into rectangles and add the costs.
- Set the Wastage. About 10% suits most rooms laid in straight rows.
- Enter the Pack coverage printed on the pack, or 0 if the flooring is sold by the square metre or cut from a roll.
- Enter the Flooring price per m² (example) and the Underlay price per m² (example) from your retailer.
- Add the Fitting price per m² (example) from a written quote, or 0 if you are laying it yourself.
- Add a lump sum for Extras (trims, door bars, beading, delivery).
- Read the total, packs and all in price per square metre, then open “Show the formula and working” to see each step.
How Much Extra Flooring Should You Buy?
Buy about 10% more flooring than the room area for most rooms laid in straight rows, and 15% for diagonal or patterned layouts. Simple rectangular rooms with few cuts can manage with 5%, while rooms with bays, chimney breasts and several doorways need more. Herringbone and chevron patterns can need 15 to 20%, so check the maker’s fitting guide, and see our flooring calculators for a pack count tuned to each floor type.
How Do You Work Out Flooring Cost Per Square Metre?
Divide the total cost by the room area to get the true cost per square metre. In the worked example below the flooring is £25 per m², but once underlay, fitting, extras and the unused part of the last pack are added, the real figure is £50.83 per m². That all in number is the one to compare between quotes, because a cheap board with expensive fitting can cost more than a dearer board laid by you.
Does Flooring Fitting Include VAT?
A fitter who is VAT registered in the UK must add VAT at the standard rate of 20% to their labour, while a small fitter below the registration threshold does not charge VAT. The GOV.UK VAT rates page lists the standard rate. Ask whether a quote includes VAT before you compare prices, then enter the fitting price including any VAT.
What Affects the Cost of a New Floor?
The four biggest factors are the flooring price, the area, the fitting price and the condition of the subfloor. Uneven or damaged floors may need a levelling compound or new boards before anything can be laid, which a quote should list separately. For the material itself, see the laminate flooring calculator or the vinyl flooring calculator for a pack count tuned to each product.
| Cost part | How it is priced | Example rate in the tool |
|---|---|---|
| Flooring | m² bought in whole packs x price per m² | £25 per m² |
| Underlay | Area with wastage x price per m² | £4 per m² |
| Fitting | Room area x fitting price per m² | £15 per m² |
| Extras | Lump sum | £40 |
| Wastage | Percentage added to the area | 10% |
All the prices in the table are examples only, not market rates. Enter the figures from your own retailer and fitter.
Worked Example: Flooring Cost for a 4 m by 3.5 m Room
Example: a living room 4 m long and 3.5 m wide gets new flooring sold in packs that cover 2 m², priced at £25 per m², with £4 per m² underlay, £15 per m² fitting and £40 of trims and door bars. These are the calculator’s default inputs.
- Area: 4 m x 3.5 m = 14 m².
- With 10% wastage: 14 m² x 1.1 = 15.4 m².
- Packs: 15.4 / 2 = 7.7, so 8 packs, which is 16 m².
- Flooring: 16 m² x £25 = £400.00. Underlay: 15.4 m² x £4 = £61.60.
- Fitting: 14 m² x £15 = £210.00. Extras: £40.00.
- Total: £400.00 + £61.60 + £210.00 + £40.00 = £711.60, or £50.83 per m² of room.
Laying the floor yourself removes the £210 fitting cost, bringing the total to £501.60.
Flooring Cost Calculator FAQs
How do I calculate the cost of flooring?
Multiply the room length by the width to get the area, add 10% for wastage, round up to whole packs and multiply the square metres bought by the price per m². Then add underlay, fitting and extras such as door bars to get the full cost.
How many packs of flooring do I need?
Divide the area with wastage by the coverage printed on one pack and round up. A 14 m² room with 10% wastage needs 15.4 m², so with 2 m² packs you buy 8 packs. Keep any unopened packs for future repairs.
Do I pay for wastage?
Yes. You pay for every pack you buy, so the wastage allowance and the unused part of the last pack are part of the cost. In the default example you pay for 16 m² of flooring to cover a 14 m² room.
Is underlay priced on the room area or the area with wastage?
The calculator prices underlay on the area with wastage, because rolls are cut to fit and some is lost at the edges. If your retailer sells underlay in whole rolls, check the roll coverage and round up to whole rolls.
Should I include skirting and beading in the cost?
Yes, if you need them. Beading or scotia covers the expansion gap at the walls, and door bars finish each doorway. Put them in the extras figure, or use the skirting board calculator if you are replacing the skirting as well.
Can I use the calculator for carpet?
Yes. Enter 0 as the pack coverage so the flooring is priced on the area with wastage, and set the wastage to allow for the roll width. The carpet calculator works out roll lengths for a more exact carpet figure.
Checked October 2026. Sources: GOV.UK: VAT rates, Wikipedia: Underlay. All prices in the tool are editable examples, not market rates.