Pro calculator
Underlayment Calculator
Estimate underlayment rolls for any floor area.
How the underlayment calculator works
Underlayment is sold in rolls of 100–200 ft². Divide floor area by roll coverage and add ~5% for seams and overlaps.
Frequently asked questions
Do I need underlayment for LVP?
Most click-lock LVP over 6 mm has attached pad. Thinner planks and floors over concrete benefit from a moisture-barrier underlayment.
How is underlayment sold?
In rolls, typically 100 ft² for foam and up to 200 ft² for cork or felt.
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