Do I need underlayment for vinyl plank flooring?

Only if the vinyl plank does not have an attached pad. Many SPC and WPC products include an integrated underlayment. Adding extra padding over attached pads can void the warranty.

What underlayment is best for sound reduction?

Cork and rubber underlayments provide the best sound dampening. For maximum noise reduction in multi-story buildings, choose products with high STC and IIC ratings.

Floor UnderlaymentGenerating image…

Flooring

Underlayment

$0.15-$1.00 per square foot

Floor Underlayment (2026)

Prepared by Lumberama's Building Materials Team

|Last updated May 15, 2026|Sources & methodology

Floor underlayment is a thin padding layer installed between the subfloor and floating floor materials like laminate, vinyl plank, and engineered hardwood. It provides sound dampening, minor leveling, moisture protection, and cushioning comfort. Available in foam, cork, rubber, and combination materials with built-in vapor barriers.

Key Features

Sound dampening (STC/IIC ratings)
Built-in moisture barrier options
Cushioning for comfort
Minor subfloor leveling
Compatible with multiple floor types

Specifications

Materials: Polyethylene foam

cork

rubber

felt | Thickness: 1mm to 6mm | Sound Rating: STC 50-73

IIC 50-73 | Moisture Barrier: 6-mil poly film | Roll Sizes: 100-360 sq ft

Applications

Under laminate flooring
Under vinyl plank flooring
Under engineered hardwood
Over concrete subfloors
Upper-level floors for sound reduction

Installation Overview

Roll out underlayment perpendicular to the flooring direction. Butt seams together without overlapping (unless specified). Tape seams with manufacturer-recommended tape. If no built-in vapor barrier, install a separate 6-mil poly sheet over concrete subfloors.

Pros & Cons

Pros

✓ Reduces sound transmission
✓ Provides moisture protection
✓ Adds underfoot comfort
✓ Helps with minor subfloor imperfections

Cons

✗ Too thick can cause floating floors to flex
✗ Must match underlayment to floor type
✗ Some flooring has attached pad (no additional needed)
✗ Not a substitute for proper subfloor leveling

Top Brands

Shaw

Mohawk

Code Requirements

Multi-story buildings may require minimum STC/IIC ratings per building code. Moisture barrier required over concrete subfloors. Must follow flooring manufacturer specifications for approved underlayment.

Buying Tips

Check if your flooring has an attached pad before buying separate underlayment. Choose underlayment with a built-in vapor barrier for concrete subfloors. Do not double up underlayment as it can cause floor instability.