Underlayment for Vinyl Plank Flooring

Reply

  #1  
Old 12-19-10, 09:10 PM
Member
Thread Starter
Join Date: Dec 2010
Location: USA
Posts: 6
Underlayment for Vinyl Plank Flooring

I am installing some flooring and need some advice.

I bought Vinyl Plank Flooring (Novalis) recently, and had planned to install it directly over my concrete slab. It's the stuff that looks like hardwood. I chose the vinyl because of its waterproof properties and that it wears well. The concrete slab is the floor to the lower level of my bi-level home, which currently has carpet.

Fortunately, before installing the vinyl, I realized that it may be a bad idea to install it on the concrete slab because the floors will get very cold in the Winter months. I would like to find a good underlayment for vinyl plank flooring (4"x36"x3mm tiles) so that there is some insulation between the concrete and the floor, which I have found is common for radiant heating systems. Vinyl plank has unique requirements, since the underlayment cannot flex much. So far I have found these which appear to have at least some foam component:
  • Jumpax
  • Wedi board
  • Easyboard

The Jumpax seems to be an ideal solution, but it is $3.20 per square foot, which seems pretty steep for what I want. I would prefer something no thicker than 10mm or 3/8". Please let me know what you guys think.
 
Sponsored Links
  #2  
Old 12-20-10, 06:31 AM
Member
Thread Starter
Join Date: Dec 2010
Location: USA
Posts: 6
Okay so it looks like Wedi may not work, because I just found this line in the documentation:
j. wedi Building Panel is not to be used as a tile backer for flexible and soft flooring.
 
  #3  
Old 12-20-10, 03:53 PM
Member
Join Date: Jan 2006
Location: USA
Posts: 3,489
I don't think easyboard is a solution either. 1/2" easyboard cannot be used on floors. 1/4" easyboard can be used on framed wood floors, but not concrete slabs. It needs to be mechanically fastened to the floor with nails or screws. Additionally, its for ceramic tile and natural stone, not flexible flooring.

I'm not sure what Jumpax is.

Cork underlayment might work. I'm not a vinyl guy so maybe somebody else might know.
 
  #4  
Old 12-20-10, 05:25 PM
chandler's Avatar
Banned. Rule And/Or Policy Violation
Join Date: Dec 2005
Location: USA
Posts: 39,968
If your proposed flooring is anything like the Allure brand, you don't want any underlayment. Underlayment will move too much and cause a failure at the overlap seams. Lay it directly on your smooth concrete flooring. If cold is the problem use throw rugs. Underlayment won't help it get any warmer or keep it from cooling.
 
  #5  
Old 12-21-10, 07:21 AM
Member
Join Date: Mar 2008
Location: Northeast
Posts: 43
Try looking into "The Barrier" from NOFP.COM. It is 3/8" polystyrene insulator with a vapor barrier.
 
  #6  
Old 12-21-10, 12:05 PM
Member
Join Date: Jan 2006
Location: USA
Posts: 3,489
"The Barrier" goes under the concrete, not over. The op is looking for something to put over the slab.
 
  #7  
Old 12-22-10, 02:45 PM
Member
Join Date: Mar 2008
Location: Northeast
Posts: 43
You need to try thinking outside the box...or slab, so-to-speak. Here' show it lays out:
Lay out the The Barrier
Lay (shoot in or floating) out 3/4" plywood
Then the finished surface goes over the top. Insulated floor!

We've done it many times to heat UP from the slab instead of heating the earth when the slab has no insulator below it...

I know, I know, great idea!
 
  #8  
Old 12-22-10, 07:59 PM
Member
Thread Starter
Join Date: Dec 2010
Location: USA
Posts: 6
Thanks guys. Jumpax is essentially a two-part system, with the bottom being 3mm polystyrene with ~1mm aluminum sheet underneath, and the top overlapping the seams of the bottom with 6mm MDF and adhesive.

It doesn't look like The Barrier would be a good solution since it's designed to go under the slab, and more importantly it would just be too thick for my floor. I would then need to worry about door clearances and transitions.

That is an intriguing idea though, warmsmeallup. What do you guys think about 1/4" EasyBoard (or Wedi board) with 1/4" plywood over top of that? After reading into Jumpax, I don't think it would be all that different (albeit 1/8" thicker). It might flex more which would be a deal breaker.

I disagree that you should not have an underlayment, which is why I am looking into one. Check out the installation docs for any radiant flooring solution - they will tell you that you need something between the slab and the heating system (which goes under the floor), or else you are just wasting energy because the concrete acts as a heat sink.
 
  #9  
Old 12-23-10, 05:20 AM
chandler's Avatar
Banned. Rule And/Or Policy Violation
Join Date: Dec 2005
Location: USA
Posts: 39,968
You didn't mention you were installing a radiant floor heating system, only that certain insulation was suggested for such an installation. If you have radiant heating, you would need to follow their recommendations as to overlay and underlayment. Of course install one if needed. It was my understanding you wanted to use an underlayment as "insulation" which it won't. I just didn't want you spending your money on a product that would give you zero return.
 
  #10  
Old 12-23-10, 06:05 AM
Member
Thread Starter
Join Date: Dec 2010
Location: USA
Posts: 6
Thank you for the input chandler. Just to clarify, I am not installing radiant flooring; however, I was using the preparation steps as an example of how cold floors will interfere with interior heating. My impression is that insulation will keep not only the floor warmer, but prevent the cold slab from cooling the floor and the air immediately above it.
 
  #11  
Old 12-28-10, 02:52 PM
Member
Thread Starter
Join Date: Dec 2010
Location: USA
Posts: 6
If anyone disagrees with my assessment on the insulation then please chime in!
 
  #12  
Old 12-28-10, 03:33 PM
Member
Join Date: Jan 2006
Location: USA
Posts: 3,489
While I don't disagree that some sort of insulation over the slab might help, I do disagree with your choices. Both Wedi and EasyBoard are ceramic tile backers and are not meant to be used the way you intend to use them.

EasyBoard needs to be mechanically fastened and is intended for framed wood floors. It will not lay flat and stay flat on a cement slab unless you can find a way to bond or fasten it.

Wedi can be used over a slab, but must be bonded to the slab with thinset mortar. Adding a layer of plywood over it or vinyl is not what wedi was designed for. I don't see how you would get plywood to lay flat and stay flat unless you mechanically fastened it thru the Wedi to the slab.

Do yourself a favor and call the manufacturers of these products to see if your use is acceptable.

You may want to post in the vinyl flooring forum here, as I would think this is a common issue.
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
Display Modes