Property Repair Calculators

Flooring Replacement Calculator

Multiply each room’s length by its width, add them up, and add a waste allowance for cuts: about 10% for a straight layout and 15% for diagonal. [1] Divide by the square feet in a box and round up to get how many boxes to buy.

Results

Boxes to buy

300 sq ft ordered for 268 sq ft of floor

Floor area: 268 sq ft
Waste (10%): 26.8 sq ft
Area to cover: 294.8 sq ft
Boxes: 14.74 → 15

Buy boxes from the same production lot so color matches. Keep a few spare planks or tiles for future repairs.

How this was calculated

Rooms = 268 sq ft
With 10% waste = 294.8 sq ft
Boxes = 294.8 ÷ 20 = 14.74 → 15
Ordered = 15 × 20 = 300 sq ft

Worked example

A 12 × 14 ft room and a 10 × 10 ft room, straight layout, 10% waste, and flooring that comes 20 sq ft to a box.

Rooms:   12 × 14 + 10 × 10 = 268 sq ft
Waste:   268 × 1.10 = 294.8 sq ft
Boxes:   294.8 ÷ 20 = 14.74 → 15 boxes
Ordered: 15 × 20 = 300 sq ft

How the formula works

floor area  = Σ length × width
to cover    = floor area × (1 + waste %)
boxes       = to cover ÷ sq ft per box, rounded up
cost        = boxes × sq ft per box × your price per sq ft (optional)

Cost uses the square feet you actually buy (whole boxes), not the floor area, because that is what you pay for. This page does not supply prices: enter your own quote or shelf price.

Limitations

Rooms are treated as rectangles. Split L-shaped rooms into two rectangles, and add closets separately.
Waste depends on the product, plank length, room shape, and installer. The defaults come from one vinyl plank manufacturer; hardwood makers give 5–12% for standard layouts.
No sourced herringbone figure was found. The 15% starting point should be replaced with your product’s or installer’s number.
Underlayment, transitions, baseboard, and adhesive are not included.
Cost is material only at the price you enter. Installation, removal, and subfloor repair are separate.

Common scenarios

Replacing flooring after a water loss: enter every room the continuous floor runs through, not just the wet one. Floors that run between rooms without a break usually have to be replaced together to match.
Diagonal tile or plank: choose Diagonal to start at 15% waste, then adjust to your installer’s figure.
Carpet: carpet is sold off 12 ft or 15 ft rolls, so seam layout drives waste more than area. Use this for a rough area and ask the installer for a cut plan.
Comparing products: change the coverage per box to see how many boxes each product needs for the same rooms.

Common questions

How much extra flooring should I buy?

LifeProof recommends adding 10% for standard installations and 15% for diagonal. Shaw says 5–10% for hardwood depending on layout, and Mullican says 7–12%. Diagonal and herringbone layouts need more.

How much waste for herringbone flooring?

More than straight or diagonal. Shaw says herringbone requires a higher waste percentage but gives no number, and we found no manufacturer figure. Ask your installer or check your product’s instructions.

How do I calculate boxes of flooring?

Divide the square footage you need (including waste) by the square footage printed on one box, then round up to the next whole box.

Why does this page not show flooring prices?

Prices vary widely by product and region. Enter your own price per square foot to see a material total.

Sources and methodology

Waste defaults are manufacturer figures, used as editable starting points. The herringbone figure is not sourced (see limitations). No prices are supplied; cost appears only from a price you enter.

[1] LifeProof Vinyl Plank installation instructions (Home Depot). Retrieved 2026-09-25. LifeProof: “add an additional 10% to your square footage for standard installations to account for cuts.” LifeProof: “For diagonal installations, add 15%.”
[2] Shaw — Solid Hardwood installation instructions. Retrieved 2026-09-25. Shaw: “a 5 - 10% waste factor, depending on layout, must be added to the actual square footage amount needed. (Diagonal, herringboned, or bordered installations will require a higher waste percentage.)”
[3] Mullican Flooring — FAQ. Retrieved 2026-09-25. Mullican: “recommends adding 7 to 12 percent for waste and cuts, depending on the skill level of the installer and the layout of the space.”

This tool provides an educational estimate only. Insurance companies, contractors, and building officials may calculate these figures differently depending on policy language, property condition, local pricing, and applicable codes.

Disclaimer: Calculators and information on this site are provided for educational and estimating purposes only. Results do not determine insurance coverage, claim payments, repair requirements, or professional recommendations.