Underlayment Calculator
How many rolls of flooring underlayment
Adding underlayment beneath new flooring? Enter the floor area to find how many rolls to buy.
How much underlayment?
Underlayment rolls commonly cover about 100 ft². Match the floor area (underlayment runs edge to edge with minimal overlap). Some flooring has it pre-attached — check before buying.
Frequently asked questions
How many square feet in a roll of underlayment?
Commonly 100 ft², though some rolls cover 200 ft². Check the label.
Do I always need underlayment?
Not always — some laminate and vinyl come with it pre-attached. Add separate underlayment only if your flooring doesn't include it.