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Learning Center - Underlayment

Flooring Underlayment
Flooring underlayment is the major determining factor in how your new flooring will sound, feel underfoot, and even how long it will last. It’s usually required when installing floating flooring (floor that is not directly attached to the subfloor using staples, nails or glue), but that’s not always the case. For example, click vinyl planks don’t require underlayment, but it can be used to provide some cushion and impact resistance. Some flooring has attached underlayment, and that usually suffices, though some customers choose to have an extra layer for more sound absorption and support.

Underlayment is made from a variety of materials, from foam to cork. The more inexpensive underlayments are made of open cell foam and are the bare minimum of what you need. However, we wouldn’t recommend it for a heavily used room.

The premium underlayments are made of rubber, closed cell foam, and cork. These degrade at a much lower rate, offer more support, prevent heating/cooling loss, and increase the longevity of the floor.

Underlayment FAQ

  1. What if I’m installing my floating floor over concrete?
  2. What if I’m installing my floor over an existing floor?
  3. What if I’m installing my floor over plywood or OSB (Oriented Strand Board)?
  4. What if I’m installing my floor over radiant heating?
  5. Is there anything else I need to purchase other than the underlayment itself?

What if I’m installing my floating floor over concrete?
When you float a floor over concrete, it’s imperative to use a moisture barrier. The moisture in concrete evaporates and has nowhere to go but into the flooring itself. If the underlayment you choose does not have a vapor barrier, be sure to purchase one separately.

What if I’m installing my floor over an existing floor?
We wouldn’t recommend installing a floating floor over another floating floor (definitely not carpet). It’s just important the existing floor is level. You’ll also want to consider the height of the new floor compared to the floors it will transition to, and making sure you’ll have the door clearance you need.

What if I’m installing my floor over plywood or OSB (Oriented Strand Board)?
Plywood or OSB likely means there is a room underneath, a basement or a crawl space. This is where insulation and sound absorption can even be more important. For example, condominiums will require a higher grade underlayment as to keep the disturbance of the downstairs neighbors to a minimum. And if over an open crawl space, garage or basement, you’ll definitely want to consider a premium grade underlayment to prevent heating/cooling loss.

What if I’m installing my floor over radiant heating?
This is where you would actually prefer underlayment with a lower insulation value (R Value) for more heat conductivity. Be sure to check the manufacturer recommendations for whether or not the underlayment you choose is radiant heat approved.

Is there anything else I need to purchase other than the underlayment itself?
If the underlayment you choose does not have an attached moisture barrier or tape, you’ll need to purchase those items separately.

Flooring Underlayment Make the right underlayment choice

Choosing the right flooring underlayment is an important step that will affect your overall experience. And considering the amount of time you’ll have your new flooring, the extra pennies spent today can make all the difference on your satisfaction.

You can view our selection of underlayment along with a comparison chart that will help you to make the best decision for your needs. If we haven’t answered your question here, please call one of our factory trained representatives at 1-800-454-3941 and we’ll be more than happy to help.