How to use it
- Measure each room and type it as length × width, one room per line.
- Enter the Area in one pack from the box, and the total width of the door openings.
- Choose the Laying pattern. Leave Waste empty to use its allowance, or type your own figure.
- Read Packs to buy, then check the Skirting length and the Underlay area before you order.
How the packs are counted
The floor area of the rooms is added up, the waste allowance is added on top, and the total is divided by the area in one pack. The result is rounded up, because a part pack cannot be bought.
The skirting is the perimeter of each room, which is twice its length plus its width, added over the rooms, less the door openings. Underlay is shown as the floor area; the overlaps at the seams come on top.
packs = floor area × (1 + waste) ÷ area in one pack (rounded up)
skirting = Σ 2 × (length + width) − door openingsWaste allowance
Some of each board is lost to the ends that do not fit and to the offcuts at the walls. A straight lay uses the 10 % allowance, a diagonal lay the 15 % one, because each wall meets the boards at an angle and leaves offcuts that are hard to reuse.
These percentages are planning examples, not figures from a source on this page. Long narrow rooms, rooms with many corners and first-time installers need more; check the instructions of the product you buy.
What this calculator does not include
- Trims, threshold strips and the expansion gap at the walls.
- Adhesive or glue, the underlay roll's overlap tape and the damp-proof membrane on a concrete floor.
- Stairs, a stepped floor or a room that is not a rectangle, except as the two rectangles you type.
Worked example: a room of 5 × 4 m and a hall of 3 × 2 m
The two rooms are 20.00 + 6.00 = 26.00 m². With the straight-lay allowance of 10 % the area to buy for is 28.60 m².
Packs of 2.00 m² give 28.60 ÷ 2.00 = 14.3, so 15 packs. The walls total 2 × (5 + 4) + 2 × (3 + 2) = 28 m; less a door of 0.80 m, the skirting is 27.20 m.
| Straight (10 %) | Diagonal (15 %) | |
|---|---|---|
| Area to buy for | 28.60 m² | 29.90 m² |
| Packs of 2.00 m² | 15 | 15 |
Frequently asked questions
How many packs of laminate do I need for a room?
Multiply the floor area by 1.10 for a straight lay, divide by the area in one pack, and round up. A 26 m² floor needs 15 packs of 2 m² with waste added.
Should I use more waste for a diagonal lay?
Yes. A diagonal lay leaves triangular offcuts at every wall, so the 15 % allowance is used here. Long narrow rooms and hallways need more than a straight lay in any case.
Why is the skirting less than the walls?
The door openings have no skirting, so their width is taken off the total length of the walls. Enter the width of the doors you open into these rooms.
Do I need underlay under laminate?
Installed laminate floors typically float over the subfloor on a foam or film underlayment, which reduces sound and moisture, as Wikipedia's article on laminate flooring describes. Buy the underlay for the whole floor area, plus the overlaps at the seams.
Does the tool store what I enter?
No. The calculation runs in your browser and nothing you type is sent to us or stored.
Sources
Figures and text last checked on Tuesday, November 10, 2026.