How the flooring calculator works
- Room area = length × width, in square feet.
- Add waste: area × (1 + waste % ÷ 100). This covers cuts at walls, damaged boards and pattern matching.
- Boxes = total square feet ÷ square feet per box, rounded up. Stores sell flooring by the full box.
- Cost (optional) = square feet purchased × price per square foot.
For an L-shaped or irregular room, split it into rectangles, run each one through the calculator, and add the results. The square footage calculator can help with odd shapes.
Assumptions
- Each area entered is a rectangle.
- Waste is a percentage of the room area. 10% is the industry rule of thumb for straight installations, 15–20% for diagonal or herringbone patterns.
- Box counts are rounded up to whole boxes. The cost estimate uses the square footage you actually buy.
- Underlayment, transitions and baseboards are not included.
Worked example
A living room measures 15 ft 6 in × 12 ft, and the vinyl plank you like comes in boxes of 20 sq ft.
- Area: 15.5 × 12 = 186 sq ft
- With 10% waste: 186 × 1.10 = 204.6 sq ft
- Boxes: 204.6 ÷ 20 = 10.23, which rounds up to 11 boxes (220 sq ft)
Tips before you buy
- Let laminate and hardwood sit in the room for 48 hours before installing so they adjust to the temperature and humidity.
- Buy everything from the same production lot (it's printed on the box) so the color stays consistent.
- Keep one spare box for future repairs. Discontinued flooring is hard to match.
Frequently asked questions
How much extra flooring should I buy?
Plan on 10% extra for a standard straight lay in a rectangular room. Rooms with many corners, closets or angled walls, and diagonal or herringbone patterns, need 15–20%.
How do I measure a room with a closet?
Measure the main room as one rectangle and the closet as another. Calculate each separately and add the two totals together.
What is a square yard of carpet?
Carpet is sometimes priced per square yard. One square yard is 9 square feet. The calculator shows your room area in square yards too.