How to calculate how much flooring you need
- Measure the length and width of the room in feet. For circles and triangles, use the square footage calculator.
- Split an L-shape or other odd shape into rectangles and measure each one.
- Multiply length by width for each part, then add the parts to get the total square feet.
- Add a waste allowance, usually about 10 percent, to cover cuts and mistakes.
- Divide the total by the square feet in one box and round up to a whole box.
How much waste to allow
| Layout | Typical waste |
|---|---|
| Simple room, straight layout, few cuts | about 5% |
| Standard room, straight layout | about 10% |
| Diagonal or herringbone layout | 15% or more |
Rooms with many corners, doorways or closets need more. A few spare boards are also worth keeping for repairs, because the same color batch can be hard to find later.
Laminate, hardwood and vinyl plank
Laminate, hardwood and vinyl plank are usually sold by the box, with the square feet each box covers printed on the label. Enter that number as the coverage per box and the calculator rounds up to whole boxes.
Laminate also needs underlayment for the full floor area unless the boards have it attached. Vinyl plank and hardwood are cut at walls and doorways in the same way, so they need the same waste allowance.
Buying carpet instead? Work it out in carpet by the square yard.
Frequently asked questions
How do I calculate how much flooring I need?
Measure the room and multiply length by width to get square feet, then add a waste allowance, usually 10 percent. Divide that total by the square feet in one box and round up. A 180 square foot room plus 10 percent is 198 square feet, which is 10 boxes of 20 square feet.
How much extra flooring should I buy for waste?
A common rule is about 10 percent extra for a standard straight layout, closer to 5 percent for a simple rectangular room with few cuts, and 15 percent or more for diagonal or herringbone patterns. A few spare boards also help with repairs later, since the same color batch can be hard to find.
How do you calculate laminate flooring?
Laminate is sold by the box, with the square feet it covers printed on the label. Find the room's square footage, add about 10 percent, divide by the box coverage and round up to a whole box. Plan underlayment for the room's full square footage too, unless the boards have it attached.
How many boxes of hardwood flooring do I need?
Divide the square footage you need, including waste, by the square feet in one box, and round up. For 198 square feet and boxes of 22 square feet, 198 / 22 is exactly 9 boxes. With 20 square feet per box it is 9.9, so you buy 10. Box sizes vary, so check the label.
Does vinyl plank flooring need a waste allowance?
Yes. Vinyl plank is cut to fit at walls and doorways like laminate, so plan on about 10 percent extra for a standard room and more for many corners or a diagonal layout. Enter the room size and waste percentage above, then add the square feet per box from the label to get a box count.