How to use the Flooring Cost
- Measure each rectangular area separately and add them.
- Enter the pack coverage in square metres and the price per pack.
- Set a waste allowance — 10% for simple rooms, more for diagonal laying or many alcoves.
- Add underlay, beading and threshold strips to the total cost.
How the calculation works
Pack count is total area with waste divided by pack coverage, rounded up. Waste depends on layout rather than area: laying planks along the long dimension of a room produces fewer offcuts than laying across it, diagonal installations raise waste to around 15%, and every doorway, alcove and boxing adds cuts. Long narrow rooms and corridors waste proportionally more than square ones.
The material cost is often only two thirds of the job. Underlay, expansion beading, threshold strips, adhesive for glue-down systems and door undercutting all add up, and floating floors need an expansion gap around the perimeter — typically 8 to 12 mm — which is covered by beading rather than saved from the order. Timber and laminate should also acclimatise in the room for 48 hours before laying so the planks reach ambient moisture content.
Packs = ceil( (area × (1 + waste)) / pack coverage ) ; Cost = packs × price per pack + accessoriesSource: Manufacturer installation guidance for floating floors, including 8–12 mm perimeter expansion gaps and 48-hour acclimatisation.
Worked example
An L-shaped living area of 4.8 × 3.5 m plus 2.2 × 1.9 m, laminate at 2.13 m² per pack, 28.50 per pack.
- Area = 16.8 + 4.18 = 20.98 m².
- With 12% waste for the L shape: 20.98 × 1.12 = 23.5 m².
- Packs = 23.5 / 2.13 = 11.03, round up to 12.
- Material cost = 12 × 28.50 = 342.
Twelve packs at 342, plus roughly 60 to 90 for underlay, beading and threshold strips.
Frequently asked questions
How much waste should I allow for flooring?+
10% for a simple rectangular room, 12 to 15% for L-shaped rooms or where planks run across the short dimension, and more for diagonal or herringbone layouts.
Do I need to leave an expansion gap?+
Yes for floating floors — typically 8 to 12 mm around every fixed edge, including pipes and door frames. Without it the floor buckles as it expands with humidity.
Should I acclimatise the flooring first?+
Leave laminate and engineered timber in the room, in its packs, for at least 48 hours. Laying planks that are drier or wetter than the room causes gapping or lifting later.
What else should I budget beyond the planks?+
Underlay, beading or skirting, threshold strips, a damp-proof membrane on concrete subfloors, and adhesive for glue-down systems. Together they often add 20 to 30% to the material cost.
Last reviewed August 31, 2026. We review this page whenever the underlying formula, tax year, published rate or standard changes.