Home Improvement Calculator

Flooring & Tile Calculators

Underlayment Calculator

Estimate rolls or packages from net area and product-specific coverage.

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Measurements

Use project and product-specific inputs

  1. Measure floor area and enter the product coverage plus overlap/waste allowance.
  2. Choose Imperial or Metric and keep every measurement in the selected unit system.
  3. Use package capacity and price only from the exact product or supplier.

Method

How the estimate is calculated

The engine applies the entered allowance and rounds up to whole packages.

  • Required quantity remains separate from rounded purchase quantity.
  • No hidden waste, yield, density, spacing, or price is applied.
  • The TypeScript Calculator Core is the only executable formula source.

Before buying

Verify the result

Check current manufacturer instructions, design documents, site conditions, supplier units, and local requirements.

  • Re-measure critical dimensions.
  • Confirm product coverage or yield.
  • Keep a record of the assumptions shown with the result.

Calculation provenance

Code-owned calculation engine

Definition underlayment 1.0.0 uses formula coverage_package_v1 1.0.0. Editorial content and database records cannot execute or replace the formula.

Required sources

  • Schluter Systems — Product data sheet 6.1 (version 6.1)