WeekendCalc

Flooring: how many boxes, rolls and square feet to buy

Topic guide · 6 calculators · 11 guides · 25 common sizes

Flooring is sold by the box or the roll, so the job is to turn the room's square footage into boxes with enough left over for cuts. A 12 x 15 ft room is 180 square feet; with 10% waste you buy 198 square feet, or 10 boxes of 20 square feet. Straight-lay planks in a simple room can use less waste; diagonal layouts and rooms with many corners need more.

This page brings together the flooring calculators, the guides on choosing between LVP, laminate and hardwood, the mistakes that ruin a floating floor, and the trim and carpet sums that people forget until the floor is down.

Boxes of flooring by room size

For 20 square foot boxes, worked out by the flooring calculator. Check the coverage printed on your box, which varies by product.

Square feet to buy and boxes of flooring by room size
Room (feet)Floor area (sq ft)Buy with 7% wasteBuy with 10% wasteBoxes at 10%
10 x 101001071106
10 x 121201281327
12 x 121441541588
12 x 1518019319810
14 x 1622424024613
16 x 2032034235218
20 x 2448051452827

Laminate, vinyl plank and hardwood

The square footage is the same whichever floor you choose; what changes is the waste allowance and the extras. Floating floors need underlayment (some planks have it attached), transition strips at doorways and new baseboard or quarter round to hide the expansion gap. The materials list calculator counts all of it from the room size.

Flooring CalculatorBoxes of laminate, vinyl plank or hardwood for a room.Laminate or Vinyl Plank Floor Materials CalculatorBoxes of planks, underlayment, baseboard and strips for a floor.Baseboard & Trim CalculatorLinear feet and boards of baseboard or crown molding for a room.

Carpet

Carpet comes off a roll 12 or 15 feet wide, so you buy whole widths and pay for the leftover strip. A 15 x 12 ft room on a 12 ft roll needs 15.25 feet of roll, which is 20.3 square yards against 20.0 in the room itself. The carpet calculator also counts pad and tack strip.

Carpet CalculatorHow much carpet to order for a room, with roll width, seams and pad.Rug Size Calculator: The Right Area Rug for a RoomThe area rug size that leaves a border of bare floor round it, and the largest standard rug that fits the room.

Measuring odd-shaped rooms

Split an L-shaped or angled room into rectangles and triangles, work out each one and add them up. The area calculator does each shape, and the result goes straight into the flooring calculator as a total.

Square Footage CalculatorArea of a rectangle, triangle, circle, trapezoid or ellipse.

Every calculator for this topic

Flooring CalculatorBoxes of laminate, vinyl plank or hardwood for a room.Laminate or Vinyl Plank Floor Materials CalculatorBoxes of planks, underlayment, baseboard and strips for a floor.Carpet CalculatorHow much carpet to order for a room, with roll width, seams and pad.Baseboard & Trim CalculatorLinear feet and boards of baseboard or crown molding for a room.Rug Size Calculator: The Right Area Rug for a RoomThe area rug size that leaves a border of bare floor round it, and the largest standard rug that fits the room.Square Footage CalculatorArea of a rectangle, triangle, circle, trapezoid or ellipse.

Guides

Other guides that use these calculators: Common Mistakes When Hanging Wallpaper (Rolls and Pattern Waste) · Common Mistakes When Tiling a Floor (Waste, Boxes, Grout) · How Many Lumens Do I Need? Lumens per Square Foot for Every Room · How Many Tiles Do I Need? Tiles per Square Foot and by Room Size · How Many Tubes of Caulk Do I Need? Feet per Tube by Bead Size · How Much Crown Molding Do I Need? Feet, Pieces and Corners · How Much Wainscoting Do I Need? Boards, Planks and Cap Rail · How Many Sheets of Plywood Do I Need? 4x8 Sheets by Area · How Many Square Feet in an Acre? Lot Size Chart and Conversions · How Much Epoxy Resin Do I Need? Tabletop, River Table and Coats

Answers for common sizes

Already know the size? These pages give the worked answer for one common size each, with the inputs filled in so you can adjust them.

10 × 10 ft room6 boxes at 20 ft²10 × 12 ft room7 boxes at 20 ft²12 × 12 ft room8 boxes at 20 ft²12 × 14 ft room10 boxes at 20 ft²12 × 16 ft room11 boxes at 20 ft²14 × 14 ft room11 boxes at 20 ft²14 × 16 ft room13 boxes at 20 ft²15 × 20 ft room17 boxes at 20 ft²16 × 20 ft room18 boxes at 20 ft²8 × 10 ft room80 sq ft9 × 12 ft room108 sq ft10 × 10 ft room100 sq ft10 × 12 ft room120 sq ft10 × 14 ft room140 sq ft12 × 12 ft room144 sq ft12 × 14 ft room168 sq ft12 × 15 ft room180 sq ft12 × 16 ft room192 sq ft14 × 14 ft room196 sq ft14 × 16 ft room224 sq ft15 × 20 ft room300 sq ft16 × 16 ft room256 sq ft16 × 20 ft room320 sq ft20 × 20 ft room400 sq ft20 × 24 ft room480 sq ft

Project planners

Planning the whole job rather than one material? These step-by-step planners put the calculators above in the order you will need them.

Planning to paint a room or a housePaint, primer, trim, caulk, wallpaper and board and battenPlanning new floors and tileSubfloor, underlayment, flooring or tile, grout, trim and carpetThe small jobs for a first home or a rental refreshPaint, caulk, lighting, trim, flooring and drafts

Frequently asked questions

How much extra flooring should I buy?

Ten percent is the usual allowance for straight-lay planks in an ordinary room. Use 5 to 7% for large simple rooms and 15% for diagonal layouts, herringbone or rooms with many corners.

How many boxes of flooring for a 12 x 15 room?

10 boxes of 20 square feet, covering 198 square feet with 10% waste on the 180 square foot floor.

Do I measure closets and under appliances?

Measure closets, yes. Under fixed cabinets and islands, no. Under a fridge or range, most people run the floor through so the appliance can come out later.

Should I keep spare boxes?

Keep at least one unopened box. Colors change between production runs, and a spare box makes a damaged plank an easy fix years later.

Related topics

Tile: how many tiles, and how much grout and thinsetFloor and wall tile, grout, thinset, backer board and caulk.Paint: how much you need, inside and outRooms, ceilings, trim, house exteriors, decks and wallpaper.

Estimates only. Quantities depend on your materials, site and supplier, so check coverage and sizes on the label. Follow local building codes for anything structural. How we calculate.