Short answer: floor area plus 7–10% waste for laminate and vinyl (10–15% for hardwood), divided by the coverage of one pack and rounded up to whole packs.
Step 1 — Measure the room
Measure wall to wall at the widest points, including under door casings and into closets you will floor. Irregular rooms: split into rectangles and add the areas.
Step 2 — Choose the waste
| Material / layout | Waste |
|---|---|
| Laminate and vinyl | 7% |
| Engineered wood | 8% |
| Solid hardwood | 10% |
| Diagonal layout | +8% |
| Herringbone | +13% |
Step 3 — Packs, underlay and baseboard
packs = ⌈area × (1 + waste) ÷ coverage per pack⌉
underlay rolls = ⌈area × 1.05 ÷ roll coverage⌉
baseboard pieces = ⌈(perimeter − doorways) × 1.10 ÷ piece length⌉
underlay rolls = ⌈area × 1.05 ÷ roll coverage⌉
baseboard pieces = ⌈(perimeter − doorways) × 1.10 ÷ piece length⌉
Example: a 15 × 12 ft room (180 ft²) with straight laminate: 180 × 1.07 = 193 ft² ÷ 20 ft² per pack = 9.6 → 10 packs. Perimeter 54 ft minus one 3 ft doorway = 51 ft × 1.10 = 56 ft ÷ 8 ft pieces → 8 pieces of baseboard.
Underlay: when you need it
- Laminate: almost always, with a vapour barrier over concrete.
- Click vinyl (SPC/LVP): many planks have a pad attached — adding another can void the warranty.
- Glue-down vinyl: none; follow the adhesive maker’s instructions.
Common mistakes
- Buying exact area. Cuts, defects and mistakes always eat material.
- Mixing batches. Buy all packs together and keep one sealed pack for repairs.
- Forgetting the expansion gap, which the baseboard hides.