How to calculate flooring
- Measure the length and width of the room. For L-shaped rooms, split them into rectangles and add the results.
- Enter the coverage per box printed on the packaging, in m² or sq ft.
- Choose the extra allowance: 10% for most rooms, 15% for diagonal layouts or many doorways.
- Read the number of boxes to buy and the total coverage.
About the waste allowance
Laminate, vinyl plank and engineered wood come in boxes that cover a fixed area, typically 1.5–2.5 m² (16–27 sq ft). Planks cut at the end of each row, around door frames, pipes and hearths, and the occasional damaged board all use extra material, so installers add a margin. A straight layout in a simple rectangular room wastes little, around 5–7%; herringbone, diagonal layouts and rooms with many corners can waste 15% or more.
Buy all boxes from the same batch, keep one spare box for future repairs, and let the flooring acclimatise in the room for 24–48 hours before installing. Remember underlay, which is sold separately by area, and transition strips for doorways. The calculator runs in your browser.
FAQ
How much extra flooring should I buy?
About 10% for straight layouts, 15% or more for diagonal or herringbone.
Do I measure into door frames and alcoves?
Yes. Include every area that will be covered.
Can I return unopened boxes?
Many stores accept unopened boxes, so buying a little extra is low risk. Check the store's policy.