How many packs of laminate do I need?
Divide the floor area by the area of one plank to get the number of planks, add a waste allowance for cuts at the walls and the ends of each row, and round up to whole packs. Laminate packs typically hold 8 to 10 planks, around 2 m², so rounding alone can add a noticeable amount — the results show exactly how many square metres you are buying and how much will be left over.
Waste depends on the laying pattern. A straight pattern needs about 7%, because the offcut from the end of one row usually starts the next. Diagonal laying needs about 12% and herringbone about 15%. Increase the allowance for rooms with many corners, pillars or door frames.
Precise count by row simulation
For rectangular rooms laid straight, switch on the precise count. The calculator lays the floor row by row: it allows for the expansion gap at each wall, reuses the offcut from each row end when it is long enough, enforces a minimum stagger between rows, and adds a 2% damage allowance. It also warns you when the last row would be a thin sliver, so you can split the difference between the first and last rows. You get both counts and buy the larger one.
The laminate formula
N_net = A × 10⁶ ÷ (L × W), packs = ⌈ N_net × (1 + waste) ÷ planks per pack ⌉
A is the floor area in m², L and W the plank length and width in mm. Skirting boards = ⌈ P_sk × 1.10 ÷ board length ⌉, where P_sk is the perimeter minus door widths.
Worked example
- Room 5.0 × 3.6 m = 18 m², laminate 1380 × 193 mm, 8 planks per pack, straight, 7% waste.
- N_net = 18 × 10⁶ ÷ (1380 × 193) = 67.58 planks; with waste 72.31 planks.
- Packs: ⌈72.31 ÷ 8⌉ = 10 packs = 80 planks = 21.31 m².
- Skirting with one 0.8 m door: perimeter 17.2 m, skirting length 16.4 m, plus 10% = 18.04 m → 8 boards of 2.4 m.
Underlay and vapour barrier
Floating laminate needs an underlay for impact sound and to even out small irregularities, unless the planks have one attached. Underlay is calculated as the floor area plus 5% and rounded to rolls or packs. On a screed or concrete base, a 0.2 mm PE vapour barrier protects the laminate from residual moisture; it needs 200 mm overlaps and turns up the walls, so 15% is added, along with tape for the joints.
Skirting boards and door profiles
The expansion gap around the edge is covered with skirting. The skirting length is the room perimeter minus door openings, plus the perimeter of anything fixed in the room that needs skirting around it. Ten percent is added for mitre cuts, and the total is rounded to whole boards of 2.4, 2.5 or 2.7 m. Corner pieces, end caps and adhesive or clips can be added too. Each doorway gets a transition profile, and short doorways are combined into stock lengths of 0.9, 1.8 or 2.7 m when the cuts fit.
Frequently asked questions
How much extra laminate should I buy?
About 7% for a straight pattern in a simple room, 12% for diagonal and 15% for herringbone. Keep any spare pack for future repairs.
Which way should laminate run?
Usually parallel to the longest wall or towards the main light source. The laying direction matters for the precise row count, so set it to match your plan.
How big should the expansion gap be?
Typically 8–10 mm for laminate and 12 mm or more for engineered wood, at every wall and fixed object. Larger rooms may need more; check the manufacturer’s instructions.
Do I need underlay if my laminate has one attached?
No. Tick “integrated underlay” and it is removed from the list. You may still need a vapour barrier on a mineral subfloor unless the attached underlay includes one.