Estimate carpet waste from room area and an allowance, or from rectangular room dimensions, roll width and strip direction. Select waste area, allowance percentage, room area or the roll-layout estimate. Waste percentage is relative to room area; the layout excludes extra trimming, pattern matching and reuse of offcuts.

Waste percentage is an allowance added to room area. Confirm the allowance for your project.

Illustrative choices, not recommendations by room shape.

Related Calculators

Carpet Waste Formula

The following formula is used to calculate the carpet waste.

W = (A × P) / 100

Variables:

  • W is the carpet waste (square feet)
  • A is the total area of the room (square feet)
  • P is the percentage of waste (%)

To calculate the carpet waste, multiply the total area of the room by the percentage of waste, then divide the result by 100. This will give you the amount of carpet waste in square feet.

What Is Carpet Waste?

Carpet waste refers to the leftover material or discarded items from the production, installation, and removal of carpets. This includes offcuts, underlay, and old carpets that have been removed from homes or commercial properties. Carpet waste is a significant environmental issue as it often ends up in landfills and is not easily biodegradable. It can also release harmful chemicals when incinerated. Recycling or repurposing carpet waste is a more sustainable option, but it can be a complex and costly process.

How to Calculate Carpet Waste?

The following steps outline how to calculate the Carpet Waste using the formula: W = (A * P) / 100

  1. First, determine the total area of the room (A) in square feet.
  2. Next, enter the waste percentage (P) as a percentage number: enter 10 for 10%, not 0.10.
  3. Next, use the formula W = (A * P) / 100 to calculate the carpet waste in square feet.
  4. Finally, calculate the Carpet Waste.
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

total area of the room (A) = 500 square feet

percentage of waste (P) = 10%. Therefore W = 500 × 10 / 100 = 50 square feet, and room area plus waste is 550 square feet. The 5%, 10%, 15% and 20% shortcuts are illustrative allowances, not recommendations based solely on room shape. In the roll-layout mode, strips = ceiling(room span ÷ roll width), purchased area = strips × roll width × strip length, and waste = purchased area − room area. Confirm a real cutting plan and purchase quantity with your installer.