Underlayment for Glue Down Engineered Hardwood Floors?

4 years ago

We recently purchased some engineered hardwood floors and we've been trying to decide whether we should do floating vs. glue down installation.

Our house is two stories, but majority of the engineered hardwood will be installed on the second level. We want to ensure that if you're on the ground level, you won't be able to hear much footsteps (we also have a dog) or any conversation noises.

What underlayment is good for glue down installation engineered hardwood floor?

Is Cork underlayment good?

Thanks,

Jackson

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Comments (3)

SJ McCarthy
4 years ago
I like 1/4" (6mm) cork underlayment as a double stick install in a home. Of course a double-glue down install makes for a large jump for installation costs. Instead of the usual $3/sf install for a normal glue down (labour costs) this jumps to $5 - $6/sf.

The upstairs would benefit from the double stick...the downstairs needs to be evaluated. What is your substrate for the lower level? Is it wood-joist construction (such as over a basement) or is it on a concrete slab.

If it is on slab, you will need to have the slab assessed for moisture. If there is ANY suggestion that a glue down should NOT be attempted, I would float both the cork and the floor and be done with it.

A floating hardwood floor over top of floating cork (nothing is glued to anything else) is one of the cheaper ways to get cork underneath engineered hardwood.

And be aware your material costs go UP when you glue cork underneath a glue down hardwood. The amount of glue you MUST order goes UP! Way up!

Look at your budget and decide what you can afford. And if you are on concrete, remember that you MUST spend money on the preparation. A poorly prepared substrate will create a poorly installed floor - regardless of the method of install.
Jackson Chou thanked SJ McCarthy
Jackson Chou
Original Author
4 years ago
Thanks so much for the insightful responses, @SJ McCarthy!

The substrate for the lower level is wood-joist construction (over half of our second floor is above the garage).

I do have some follow up questions:

When you mentioned double stick -- this means gluing the cork to the subfloor and then engineered hardwood to the cork right?

If I was to use floating installation, I think I would use a foam underlayment instead of cork.

For Floating vs. Glue installation method, which one provides the best soundproofing? Will either method feel weird when walking over it barefoot?
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SJ McCarthy
4 years ago
last modified: 4 years ago
Floor Muffler is OK for noise...not that great for warmth. Your link shows a 25' sf roll for $135. That = $5.40/sf for underlayment. Wow! I've NEVER seen underlayment that is that expensive! Holy cow! I'm in the wrong business.

And the product is 2mm thick. My suggestion for cork underlayment = 6mm = $0.90/sf.

If you are in Canada = www.cancorkfloor.com

USA = www.icorkfloor.com

Trust me...the 6mm cork is a much better value.

If you are FLOATING a floor you FLOAT the cork. That is to say you simply lay down the sheet of cork (3ft x 4ft rectangle of cork) and butt the edges together. No tape. No glue. Nothing. It just sits there. Contractors love it because it is SOOOOO fast and easy to deal with.

You are welcome to pay $5+ per square foot on 2mm worth of foam. Or you can pay $0.90/sf on 6mm worth of cork. It's your call.

Underlayment for Glue Down Engineered Hardwood Floors?

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SJ McCarthy

Jackson Chou
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Underlayment for Glue Down Engineered Hardwood Floors?

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Jackson Chou
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