FanFold XPS Flooring Underlayment for Laminate & Engineered Hardwood Cover more floor in less time. This fanfold XPS underlayment unfolds into wide 46.7" panels that cover 100 square feet per box — fewer seams, less taping, and faster prep than rolled foam. The rigid extruded polystyrene (XPS) core smooths minor subfloor imperfections and creates a firm, stable base for floating laminate and engineered hardwood floors. Built-In Moisture Protection The closed-cell XPS construction acts as a moisture barrier between your subfloor and finished floor — a must over concrete slabs, basements, and ground-level installs. Skip the separate vapor film and protect your floor's locking system from subfloor moisture in one step. Quieter Floors, Warmer Rooms With a 72 IIC / 67 STC sound rating and a 22 dB Delta IIC, this underlayment cuts the hollow sound and footstep noise common with floating floors — a strong choice for upper levels, condos, and multi-family projects with sound requirements. The XPS core also delivers an R-value of 5.0 per inch, adding a thermal break that keeps floors warmer over concrete. Radiant Heat Ready Compatible with both electric and hydronic radiant heat systems, so you can pair it with heated floors without compromising performance. Fast, Pro-Friendly Installation Panels lay flat right out of the box, cut cleanly with a utility knife, and tape at the seams. No adhesives, no special tools. One box, one installer, one room knocked out before lunch. Where it works best: Floating laminate and engineered hardwood floors Concrete, plywood, and OSB subfloors Basements, condos, and multi-story homes where sound and moisture matter Radiant heat installations (electric or hydronic) Not for use with: flooring that has pre-attached underlayment pad. Backed by a 25-year residential and 5-year commercial warranty.
