Flooring Calculator
Floor area for rectangular or L-shaped rooms, waste for the lay pattern, whole boxes to buy and the baseboard you will need around it.
- L-shaped rooms
- Waste by pattern
- Baseboard length
- Embeddable
Your estimate
Straight lay, 10% wasteat 20.0 sq ft per box
Area
Trim
Order whole boxes from one dye lot, and keep a spare box for repairs. Underlayment and transitions are priced separately.
Flooring is sold in boxes that cover a fixed number of square feet, and the box is the only unit the store will sell you. That makes the estimate simple in principle: floor area, plus a waste allowance for cuts, divided by the coverage on the carton, rounded up. The waste allowance is where estimates go wrong, because it depends on how the floor is laid, not just how big the room is.
How the flooring estimate works
- Floor area = length x width, less the cut-out corner for an L-shaped room.
- Add the waste allowance for the pattern.
- Boxes = area with waste / sq ft per box, rounded up.
- Baseboard = room perimeter, less about 3 ft for each doorway.
How much extra flooring to buy
There is no industry standard waste figure, but the common guidance is consistent: about 10% for a straight lay, 15% for diagonal, and up to 20% for herringbone and other patterns where almost every piece is cut. Lowe's own hardwood instructions call for 5% on a standard install and 10 to 15% on a diagonal, and tile guides use the higher numbers because tile cannot be trimmed and reused as easily.
Go higher than the pattern suggests for rooms with lots of corners, closets and doorways, and for products with long planks, where an offcut from one end of a row is often too short to start the next.
Buying tips that save a second trip
- Buy every box from the same production lot. Color and gloss vary between lots.
- Keep one spare box after the job. A damaged plank in five years is easy to replace from your own stock and hard to match from the store.
- Let the flooring acclimate in the room for as long as the manufacturer says before installing.
- Underlayment, transition strips and stair nosing are separate purchases, measured separately.
Frequently asked questions
Primary references
Manufacturer and industry guidance used to check this article.
Product instructions, tested assemblies and local code take priority over general guidance.