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Flooring Calculator

Every room in one go, and the boxes nobody else works out.

An estimate of quantities — box coverage varies by product; type yours.

1' 6" · 18 in · 1.5 ft · 0.4572 m

10' · 120 in · 10 ft · 3.048 m

15 ft²

Inch Calculator advises about 10% for tile laid straight, which is where this starts; 15% for diagonal, and Alpine 10-15% for herringbone. Mullican advises 5% for wood laid straight. It is added once, to whatever gets cut — the tiles or the planks, and the baseboard. A grout or mortar figure, where the page has one, is worked out on the surface as laid.

This page recalculates as you type. There is no Calculate button.

Answer

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Boxes

1 × 20.5 ft² box

15 ft² of floor · 1 boxes

Area to tile 15 ft²
Ticked items cost $75.00
More numbers
With the 10% for cuts 16.5 ft²
Underlayment 15 ft²
DrawingThe project drawn to scale. Area 1: 1' 6" × 10'.1' 6"10'Area 1

Buying noteBuy the spare box with the rest, out of the same dye lot. A box bought a month later is a slightly different color, and nobody tells you until it is on the floor.

Breakdown

Surface Measurements Qty Area Share
Area 1 1' 6" × 10' Add ×1 15 ft²

What to buy

Buying noteBuy the spare box with the rest, out of the same dye lot. A box bought a month later is a slightly different color, and nobody tells you until it is on the floor.

Shopping list

1 1 × 20.5 ft² box $53.00 Reference price $53.00. Type your store's. Reference price $48.00. Type your store's. Reference price $95.00. Type your store's.
1 1 × 100 ft² roll $22.00 Reference price $22.00. Type your store's. Reference price $38.00. Type your store's.
Ticked items $75.00

Untick what you already have. Each row has its price beside it — type what your store charges.

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How this was worked out

Every number below is yours. Each constant links to the row where you can change it.

Area 1 1' 6" × 10' 15 ft²
With the waste for cuts 15 ft² × (1 + 10%) 16.5 ft²
Boxes to buy 16.5 ft² ÷ 20.5 ft² 1 × 20.5 ft² box · 4 ft² left over
Underlayment 15 ft² × 1 15 ft² → 1 × 100 ft² roll

Change:Underlayment per unit area

What it comes to 1 × $53.00 + 1 × $22.00 $75.00

Assumptions

Every one of these is editable. Change one and the answer changes with it.

Assumption Value Confidence
Underlayment per unit areaUnderlayment covers the floor once. Rolls with a self-adhesive lap seam are butted rather than overlapped, so there is no second allowance here the way there is under a roof. A roll's printed area is its usable area. ≈ ft²/ft² Trade convention

Flooring for a whole floor, not one room

Flooring is bought once for the whole job, so the question is almost never about a single room. This page opens on two: a 16 by 13 foot living room and a 4 by 12 foot hallway. That is 256 square feet, 268.8 with the 5% a straight lay takes, which is 14 boxes at 20.5 square feet each.

Add a part for each room and the areas add up. Rooms with an L in them, a bay or a chimney breast are their own shapes in the picker, and a closet you are not flooring is a part with the minus sign.

Boxes, which is the step everyone stops before

Every flooring calculator will give you square feet. The number you carry to the counter is boxes, and that is a different number, because a box covers a fixed area and you cannot buy two thirds of one.

Omni's own worked example is the first of this page's two rooms: 16 by 13 feet, 208 square feet, 5% waste, 218.4 square feet. Correct, and then it stops. At 20.5 square feet a box that is 10.65 boxes, which is 11. Inch Calculator takes up to ten rooms and a waste figure and stops in the same place.

Box coverage varies, so check yours

Flooring Box here
Vinyl plank (LVP)20.5 ft²
Laminate20 ft²
Hardwood20 ft²

These are the figures the page starts from, and they are starting points. Real cartons run from about 16 to over 30 square feet depending on plank length and thickness, and the number is printed on the box. It is a box in the assumptions below for exactly that reason: the one piece of data that decides your answer is the one on the carton in front of you.

Buy the spare box with the rest

Not after. Flooring is made in dye lots and printed in batches, and a box bought a month later is a slightly different color and sometimes a slightly different thickness. One spare box, bought at the same time, is what you patch with in five years when something gets dropped. Mullican advises one to two spare boxes on top of the waste figure, and that advice is cheap to take.

What else the job needs

Underlayment, if the floor is floating — the page counts it off the same area and puts it on the list. And baseboard or shoe moulding round the perimeter, because a floating floor has to move under its trim rather than be pinned by it. Both are rows you can untick.