How many boxes of flooring do I need?
Multiply each room's length by its width and add the rooms together. Add waste for cuts and end pieces, divide by the square feet in one box, and round up. Flooring is only sold in full boxes.
Boxes = room sq ft × (1 + waste %) ÷ sq ft per box
A 15 × 12 ft living room is 180 sq ft. With 10% waste you need 198 sq ft. Laminate at 20 sq ft per box is 198 ÷ 20 = 9.9, so 10 boxes. You'd also need 2 rolls of 100 sq ft underlayment, and 8 pieces of 8 ft quarter round for 51 ft of wall (the 54 ft perimeter less a 3 ft doorway, plus 10% for miter cuts).
Waste and underlayment by flooring type
| Flooring | Typical waste | Underlayment |
|---|---|---|
| Laminate | 10% | Foam roll, unless the pad is attached |
| Vinyl plank (LVP) | 10% | Usually attached; check before adding more |
| Engineered hardwood (floating) | 10% | Foam or cork roll |
| Solid hardwood (nail-down) | 10–15% | Felt or rosin paper |
Use 5% for a simple rectangular room with long straight runs, and 15% for diagonal or herringbone layouts. Box sizes vary by product, so enter the sq ft printed on your box. Over concrete, most floating floors also need a vapor barrier; follow the maker's instructions.
Laminate flooring calculator
Laminate is a floating floor. It clicks together over a foam underlayment, typically sold in 100 sq ft rolls. The 15 × 12 ft room above takes 10 boxes and 2 rolls. Leave the expansion gap the maker specifies at every wall; the quarter round or baseboard covers it.
Vinyl plank flooring calculator
Most vinyl plank (LVP) has a pad attached, so the calculator leaves underlayment off. The same 180 sq ft room at 22 sq ft per box needs 198 ÷ 22 = 9 boxes exactly. When the math lands right on a whole box, buy one more if you can: a single bad plank leaves you short.
Sheet vinyl is different. It comes in 12 ft wide rolls like carpet, so price it by the square yard.
Hardwood flooring calculator
Solid hardwood is nailed down over felt or rosin paper. Engineered hardwood can be floated, glued or nailed. A 14 × 12 ft bedroom is 168 sq ft, or 184.8 sq ft with 10% waste: 10 boxes at 20 sq ft. Short boards and defects add up with hardwood, so many installers use 10–15%. Let the wood acclimate in the room before you install it, as the maker specifies.
Transitions and trim
Enter the number of doorways in each room that meet a different floor. Each gets a transition strip. Trim is the room perimeter less 3 ft per doorway, plus 10% for miters, in 8 ft pieces. Rooms entered as square feet are treated as square, so measure trim separately for odd shapes.
Pricing a flooring job
Installers usually quote labor per square foot, with extras for removing old flooring, leveling the subfloor, moving furniture and stairs. Materials are often billed at cost plus markup. Use contractor mode to add your labor and markup, then send it with the estimate template.
Questions
How many boxes of flooring do I need for a 10 × 10 room?
100 sq ft plus 10% waste is 110 sq ft. At 20 sq ft per box that's 5.5, so 6 boxes. Check the sq ft on your box, since sizes vary.
How much extra flooring should I buy?
Typically 10% for a standard room, 5% for large simple rooms, and 15% for diagonal or herringbone layouts. Keep a spare box for repairs.
Do I need underlayment for vinyl plank?
Usually not if the planks have a pad attached. Adding a second layer can void some warranties, so check the maker's instructions.
How do I measure an L-shaped room?
Split it into two rectangles and add each as its own room. The calculator adds them together.