Flooring Cost Estimator

Extension flooring is priced two ways, and a quote that hides the split is hard to check. There is the material supply rate per m², and there is the installation labour on top. Supply for LVT runs £15 – £60 per m2, engineered wood runs £40 – £80 per m2, and porcelain tiles run £20 – £60 per m2. Add fitting and the installed all-in rate lands at £50 – £75 per m2 for LVT, £50 – £100 per m2 for engineered wood, and £50 – £120 per m2 for porcelain.

This estimator takes your floor area and material, then splits the cost into a supply figure (with a wastage allowance for offcuts) and an installation figure. You see the two halves separately, so you can hold a flooring specialist quote against a realistic cost per m² instead of accepting one lump sum.

What the estimate covers

The result is the finished floor: the material plus the labour to lay it. It does not include the layers underneath. The screed, any self-levelling compound to correct an uneven surface, and the underfloor heating loops are all earlier, separate costs. Keep those on their own budget lines so nothing gets counted twice.

Installation labour is added on top of the supply rate, and it varies by material. Click-lock LVT is quick to lay, so its labour line is modest. Porcelain is slow, precise work that needs a specialist, which is why a tiled floor costs more to fit than its supply price alone suggests.

Choosing a material changes the rate

Material choice moves both halves of the cost. LVT is the most common pick for open-plan kitchen extensions because it is warm underfoot, water-resistant, and sits comfortably within the floor covering thermal resistance limit for underfloor heating. Engineered wood gives a real timber surface and works over UFH, though it is more sensitive to moisture near a sink or dishwasher. Porcelain is the most durable finish and the best conductor for UFH, at the price of the slowest fit. Solid hardwood is the outlier: it is not suitable over underfloor heating and needs acclimatising in the room before laying, so most extension owners choose engineered wood instead.

One planning point that sits outside the price: your floor build-up affects the finished floor level, so the finish has to be chosen before screeding so the levels line up with the existing house at every doorway.

A worked example

Take a 30m² open-plan kitchen extension floored in LVT. At the supply rate of £15 – £60 per m2, plus a wastage allowance for cuts around units and doorways, and installation labour on top, the calculator lands the job near the installed benchmark of £50 – £75 per m2. Read the total off the widget above once you enter your own area rather than working from a fixed figure.

Now swap to porcelain across the same floor. The supply rate of £20 – £60 per m2 is not far off LVT, but a tiler works slower than a floor layer, so the installed rate climbs toward £50 – £120 per m2. That gap is labour, not material, and it is exactly why a floor priced only on the supply cost of the tiles will read low against a real quote. For a full tiled-floor breakdown, the tiling estimate goes deeper on adhesive, grout, and membrane.