Is underlayment required with laminated flooring?
Yes. Underlayment provides protection against warping from moisture beneath, particularly if you're installing the floor over concrete. Underlayment also reduces or eliminates "hollow" sounds generated from traffic on the floor. Keep in mind that some laminate floors come with underlayment attached. However a "rolled out" or separate underlayment can provide greater sound absorption and moisture protection than laminate floors with one attached.