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Underlayment Calculator — Free Online Calculator

Estimates the amount of floor underlayment material needed.

What is it?

The underlay calculator works out how many rolls you need to lay under laminate or engineered flooring, based on the room area.

Formula

Rolls = ⌈area × 1.1 / (roll width × roll length)⌉ A standard roll is 1.0 × 15 m = 15 m².

Example

30 m², 10% waste, 1.0 × 15 m rolls. Area with waste: 33 m². Rolls: ⌈33 / 15⌉ = 3.

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