Floating Laminate floor question
 

Hey all,

I'm installing a new floating laminate floor in our sunroom. Its a concrete slab. Along with it I will be doing electric floor warmers so naturally due to the warmers and concrete there is a vapor/insulating barrier on the floor first.

So my question is - the floors we like have a 2mil attached pad preinstalled on them. Is it okay to have the underlayment and then install a floor with an additional underlayment? (4mm total)

I don’t see why not. As long as you have a solid and reasonably flat substrate the floor doesn’t care what it is installed over.

It will be fine. The more insulation the better

What system are you using under the floor?

Are you using Floor and Decor? I se there are stores near you. We like NuCore, and strongly do not like AquaGuard. As in will never use again.

For our downstairs bathroom we used Ditra covering then heated flooring and stone. This allows the concrete to breath as well. I’ve never been a fan of plastic right on concrete due to its’ porosity.

I’m using quietwarmth electric. Very thin system.

As far as flooring Were looking at mohawk/pergo.

Underlayment is roberts air guard. Breathable but with a vapor barrier

Check how water affects the laminates you are looking at. Some brands tend to act like a sponge and the edges swell when wet and then look like crap.

My Pergo does fine. I used a different brand (don't remember the brand) in a small sunroof that was terrible.

Well unless you buy vinyl they are all “water resistant”. . The room is dry and the underlayment is designed specifically for below grade concrete floor.

Vinyl click lock would be good if I expected a lot of wet, but part of the rehab was all new windows, weather sealing, and is above grade by 12”

Some of the underlayment pads are designed to allow some airflow, routing away any moisture.

Chris
I've been thru lots of floors in my concrete slab home over the years,from real wood to engineered wood / laminate. We finally installed the LVP (luxury vinyl plank) over a moisture proof paint & a 4 mil visqueen vapor barrier. I highly recommend it. It is scratch proof, water proof and beautiful. Make sure you go with a high quality/name brand whatever floor you pick. There is a lot of questionable flooring being sold.
Dave

Thanks. My logical side tells me thats a better way to go...

Recommend the 10 mm thick stuff. It seems to lay better and the joint edges are larger too.

Keep in mind that the thicker the underlay, the less efficient the heating source above the slab will be.
10 mm - you might not feel the heat at all ?
Bill K

I vote LVT, it looks better than laminate, is not slippery like laminate, is water proof unlike laminate. And, unlike any laminate, the good stuff carries a life time warranty. Use any mil visqueen (loose layed). Though LVT is waterproof, it blocks any possible hydrostaticaly transferred mineral buildup that can come from the slab up through the seams of the planks. I've seen it happen. The electric radiant heat mats lie on top of the visqueen and I would recommend a cushioned backed LVT product on top of that. A forever floor.
Of the many disadvantages of laminate, the biggest problem is water from the top not the bottom. Potted plants, pet water bowls, heavy mopping or a plumbing leak. Ponding water will find its way into the seams and swell the particle board or MDF core material and the seams are puckered forever. This will not happen with LVT.
I stopped selling laminate 25 years ago, too many call backs that were not my fault. My guys will install someone's laminate they bought elsewhere but not without signing a waiver of our responsibility for what happens down the road to their crappy floor covering. I'm a licensed flooring contractor in CA with 50 years experience for what that's worth

I would talk to the manufacturer of the laminate. Laminates aren't all the same with regard to adhesives, etc.

Excellent post.

Wood laminates are really coming back to haunt people that put them in 15 years ago or so. Agree with everything said above.

Call China?
Laminates are all manufactured using copious amounts of adhesives causing the product to gas off formaldehyde for years. LVT is not made this way

What’s the difference between LVPlank (click lock) and LVT?

LVP is a longer "plank" . LVT is square or rectangular "tile". Same material.