- Length × width for each rectangle. Split L-shaped rooms into rectangles.
- Add 10% waste (straight lay), 15%+ for herringbone, diagonal or lots of angles.
- Divide by the square feet per box and round up.
- Stairs are counted per step, not in square feet.
Step by step
- Sketch the floor plan. Rough is fine.
- Measure each room's length and width at the widest points, in feet.
- Split odd shapes into rectangles, then multiply and add them up.
- Include closets and under appliances that will get flooring.
- Multiply the total by 1.10 (or 1.15 for patterns).
- Divide by the box coverage, then round up.
Worked example
| Area | Size | Sq ft |
|---|---|---|
| Living room | 16 × 14 | 224 |
| Dining | 12 × 10 | 120 |
| Hall | 15 × 4 | 60 |
| Total | 404 | |
| +10% waste | 444.4 | |
| Boxes at 20 sq ft each | 23 boxes (22.2, rounded up) |
Don't forget
- Stairs: count treads and risers, and the nosings separately.
- Transitions: count every doorway where the floor meets another type.
- Baseboard: measure the room perimeters if replacing.
- Keep one spare box after the job.
Want it done properly? We measure for free. Send a few photos to start.
Common questions
How do I calculate how much flooring I need?
Multiply length by width for each room (splitting odd shapes into rectangles), add them up, add 10% for waste (15% or more for patterns or diagonal layouts), then divide by the square feet per box and round up.
How much waste should I add for flooring?
About 10% for a straight layout. 15% or more for herringbone, chevron, diagonal layouts or rooms with many angles.
How do you measure stairs for flooring?
Stairs are usually counted per step (treads, risers and nosings) rather than in square feet, because each step needs its own pieces and trim.
Who's writing this: Rose and Thorn Flooring is a flooring company in Surrey, BC. We install floors for a living, so yes, we'd love to do yours. But nobody pays us to say nice things about a product, and we don't earn commission from any brand. If something here is wrong or out of date, text us at 604-716-4160 and we'll fix it.