BuildRuler

Build & DIY estimates

Flooring calculator

Quick answer: Flooring needed = room area plus a waste allowance, rounded up to whole boxes. Example: a 12 × 15 ft room is 180 sq ft; adding 10% waste gives 198 sq ft, so with boxes that cover 20 sq ft you buy 10 boxes. Use 15% waste for diagonal layouts or rooms with many corners.

  • Manufacturer bag yields · published coverage rates
  • Updated
  • Reviewed by Alex · How we calculate

Box coverage is printed on the carton.

How much extra to buy

Add about 5 to 10% for straight layouts and 15% or more for diagonal or herringbone patterns, small rooms with many cuts, or plank flooring with a strong grain match. Flooring is sold by the box, so round up to whole boxes.

Worked example

A 12 × 14 ft room is 168 sq ft. With 10% waste you need 184.8 sq ft. At 20 sq ft per box that is 9.24 boxes, so buy 10.

Before you install

Many manufacturers ask you to let wood and laminate acclimate in the room for 48 to 72 hours, and keep an unopened box for future repairs, since colours change between production runs.

Frequently asked questions

How much waste for flooring?

Around 5–10% for straight installs.

Do I measure closets?

Yes, if the flooring runs into them.

How do I measure an L-shaped room?

Split it into rectangles, work out each area and add them.