What the animation shows
The animation and the step-by-step video above use your numbers. Here is the same walkthrough written out for the default example.
What you enter
- Rooms: 12 × 15; 10 × 14 ft.
- Roll width: 12 ft.
What happens, step by step
- Carpet comes on a 12 ft wide roll, laid in full-width strips.
- This strip runs past the wall. The extra 2 ft is cut off as waste.
- The side bar is the roll you buy: 29 ft long, waste hatched.
The answer: carpet to buy is 38.67 sq yd.
How it’s calculated
- Strips = room width ÷ roll width, rounded up; length = strips × room length
- Both orientations are tested; the shorter roll length is used
- Square yards = roll length × roll width ÷ 9
Worked example
Rooms 12 × 15 ft and 10 × 14 ft on a 12 ft roll.
Inputs
- Rooms
- 12 × 15; 10 × 14 ft
- Roll width
- 12 ft
- Price per square yard
- 0 $/sq yd
Results
- Carpet to buy
- 38.67 sq yd
- Roll length
- 29 ft
- Room area
- 35.56 sq yd
- Waste
- 8.8%
Assumptions and limits
- Each room is cut separately; leftover pieces are not reused in other rooms.
- Pile direction and pattern matching are ignored. Patterned carpet needs extra.
Verify the result against the applicable local code, adopted code edition, manufacturer instructions and project requirements. See our methodology.
Questions
Why do I pay for more carpet than my room area?
Carpet comes in fixed widths. A 10 ft wide room cut from a 12 ft roll wastes a 2 ft strip along its length.
How do I convert square feet to square yards?
Divide square feet by 9.