RenoPeek

Flooring calculator

Enter the room and this returns the area to order, including waste. The waste factor is the part most estimates get wrong: measuring the floor is easy, and ordering exactly that much is how people end up half a box short on the last row.

Room and material

Order this much

Enable JavaScript to calculate, or use the formula belowArea times waste factor — the arithmetic is printed below and works on paper.

Nothing you type here is sent anywhere. The arithmetic runs on your device and the page makes no network request — see the privacy note.

The formula

Length times width gives the floor area. Multiply by one plus the waste factor and round up to whole boxes. A 14-by-12 room is 168 square feet, which at a ten percent waste factor means ordering 185 square feet.

Rooms that are not rectangles get measured in rectangles: split the floor into sections, work out each one, and add them. Closets and doorway thresholds count if the flooring runs into them, which it usually does.

Why the waste factor changes with the layout

Every cut at a wall produces an offcut, and the question is whether that offcut can start the next row. In a straight lay it usually can, so ten percent covers breakage and the odd bad plank. In a diagonal or herringbone layout the angled offcuts rarely fit anywhere else, and the same floor needs closer to twenty percent.

HomeAdvisor's published figure is 10 to 15 percent, stated for tile, to cover damage during installation and future repairs. The twenty percent row above extends that logic to patterned layouts and is a working rule rather than a figure from that source — the distinction matters, and it is why it is labeled here rather than presented as published data.

MaterialInstalled, per sq ftWhat drives the spread
Vinyl and LVP$2–$14Wear layer thickness and whether it is glue-down or click
Laminate$3–$13AC rating and core quality; the cheap end swells if it gets wet
Carpet$3.50–$11Fiber and pad; the pad is where people economize and regret it
Hardwood$6–$25Species, plank width, solid versus engineered, and finish
Tile$15–$20Substrate prep is most of it; see the tile calculator
Stone$6–$20Sealing requirements and how much of the slab is usable

What this leaves out

Taking up the old floor, which HomeAdvisor prices at $1.50 to $3.50 per square foot and which doubles if there is adhesive underneath. Underlayment at $0.50 to $5.40. Subfloor repair, which nobody can quote until the old floor is off. Transition strips, trim and quarter round. Moving furniture at $60 to $120 per hour.

On a straightforward click-lock floor over a sound subfloor those extras are minor. On a 1970s kitchen with two layers of vinyl and possible asbestos backing — HomeAdvisor puts asbestos removal at $5 to $20 per square foot — they can exceed the flooring itself.

Where flooring sits in a budget

Flooring is usually the second or third line in a room budget rather than the first, and in a kitchen it is a modest line against cabinetry. The material prices, the labor rates and the two lines that surprise people — taking the old floor up and whatever is underneath it — are set out in what flooring costs.

If the floor in question is tile, the tile calculator handles the higher waste factor that patterns need, and the remodel cost calculator gives the whole-room figure the flooring sits inside.

Questions people ask

How much extra flooring should I order?
Ten percent over the measured area is the working default for a rectangular room with straight-lay planks. Add more for diagonal layouts, rooms with many corners, or patterned material that has to line up. HomeAdvisor recommends 10 to 15 percent extra on tile specifically, to cover breakage during installation and future repairs.
How many boxes of flooring do I need?
Divide the area you are ordering, waste included, by the coverage printed on the box and round up. Boxes typically hold 20 to 30 square feet for planks. Always round up to whole boxes rather than to the square foot, because that is the unit the supplier actually sells.
Does the waste factor include the leftover box?
It should, and that is the argument for ordering at the top of the range. Keeping one sealed box after installation means a future repair matches, because dye lots change between production runs and a plank bought two years later rarely does. Treat the spare box as part of the job, not as an overspend.
What does the calculator not include?
Removing the old floor, which HomeAdvisor puts at $1.50 to $3.50 per square foot, underlayment at $0.50 to $5.40, subfloor repair, and trim or transition strips. It also excludes furniture moving, billed at $60 to $120 per hour. On a room that needs the old floor taken up, those lines can rival the material cost.
Sources