Which is Best Underlay for Laminate?
Flooring Underlayment for Laminate or Engineered Floating Floors

It depends! The answer to "which is best underlay for laminate?" really does depend on three things...

  1. Your Environment... meaning what is the subfloor where you are installing the laminate floor? Concrete underlayment is not designed for plywood subfloor applications and viceversa!
  2. What type of floating floor that you have purchased. Laminate floors with underlayment attached have different needs then a plain engineered or laminate floor.
  3. Your personal needs. Do you have a budget? Is it important to add "R" value or have a noise reduction laminate underlay?

First, it is important to realize that underlays of various sorts are designed to serve two critical purposes:

  1. Underlayments act as a cushion between uneven subfloors and the backside of your laminate or engineered floor. The typical cork, rubber or foam underlays even-out the bumps either on a pored cement slab, or typically where the plywood sheets meet on a traditional wood subfloor. This puts less pressure on the interlocking mechanism of a floating floor, and thus improve their structural integrity.
  2. In environments where heavy equipment maybe sitting on the floor, the underlay, especially commercial underlays are quite dense and help in distributing the weight load on these "slightly uneven" floors.

  3. Some underlays are also designed to prevent moisture penetration from the subfloor below into the backside of the floating floor, especially critical in "on concrete" installations.

It can also

  • provide sound dampening services between floors.
  • increase your "R" value, especially in below grade installations.
  • act as a cushioning agent to make standing and walking on floating floors a more enjoyable experience

Your Environment?
Thus if we go back to our original question of "which is the best underlay for laminate?" the first question is what is the subfloor. On-Concrete underlayment must be both a vapour barrier AND a cushion. This can be accomplished either by using a foam underlay + a polyethylene film (typically 6mm) in a layered installation, or a 2 in 1 underlayment installation like the Pergo softseal combo foam floor underlayment, Quiet WalkŪ by Midwest or Solid Walk LT- Fiber MB with lip and tape.

The latter being the most sophisticated version with a 3" extension of polyethylene film that extends beyond the fiber pad, and allows an overlap of the vapour barrier film. Cheaper "2 in 1 underlays" require the foam to be flush fitted and taped, creating a less effective vapour barrier.

In cases where the subfloor it is a traditional above grade plywood or OSB, underlayment should NOT include a vapour barrier. Wood is a biological species that likes to breath. The polyethylene films can lock in moisture and lead to mould in severe case... thus not necessary so don't use it!

That being said, Wilsonart does have a few exceptions so ask!

Type of Floating Floor?
In a similar vein, make sure you know what type of floating floor that your have bought BEFORE you purchase a laminate flooring underlayment. Many of the newer laminate floors actually have been fabricated with a foam padding incorporated into its design. These flooring products DO NOT require a foam padding. Be sure to ASK FIRST!

Your Personal Needs?
I'm not sure that I would worry about the R value of a foam as it is more of an incidental benefit than a real one. With an typical R rating of .5 for a laminate underlayment, you may want to think of other methods to achieve significant insulation value then factoring in the underlay

Noise reduction is another issue. Personally I hate the hollow sound of most floating floors, especially when my dog wants to pace all night, so I'd invest a few extra cents in a noise reduction laminate underlay, especially since the industry has developed a number of options that are significantly cheaper than the historical cork and rubber solutions. That being said it really doesn't make sense to spend .70$ on an underlay for a $1.49/sq.ft floor.

Some underlays spout about their anti-microbial additives but when I talk to industry distributors they seem to suggest that this is more of a marketing game than a real benefit.

Well that's it guys, hope this helps.. at the end of the day you probably only have a few choices of laminate underlays to pick from in your area, so use this as a guideline to select the most appropriate of the lot.

Further Information:
Install Laminate Underlayment
Noise Reduction Underlay Standards
Noise Reduction Underlay Ratings
No Underlayment Laminate Floor