# Laying down laminate flooring on a concrete floor



## poppameth (Oct 2, 2008)

It depends on your pad. If your pad has a vapor barrier with pretaped edges go ahead with the pad and then the laminate. If it does not have a moisture barrier you need plastic, then pad, then the laminate. I don't see why anyone would recommend a subfloor be installed first. If you are worried about moisture issues you should check the floor with a calcium chloride test kit, or a moisture meter at the very least.


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## jpcustoms (Sep 26, 2009)

*laminate on concrete*

i agree, use the 2 layer pad with vapor barrier, plastic meets the floor. you may want to go the extra step and use a primer on the concrete 1st, such as kilz or zinnser 123


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## poppameth (Oct 2, 2008)

If you want to prime the slab don't use Kilz or Zinsser. They are not meant for this. You could use a product such as Cutdown II by Dependable that is designed to hold back from 8 to 12 psi of water pressure, but that's probably not necessary in your situation.


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## jpcustoms (Sep 26, 2009)

*laminate on concrete*

thks pappa
will check into the cutdown stuff next time i run across a similiar situation.


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## MinConst (Nov 23, 2004)

Best case.
Seal slab with a concrete sealer. SW has a decent one.
Lay 6-8 mil poly on top.
Lay vapor barrier padding best you can get.
Lay Lam.
Second best
forget the sealer
Worst case
Lay with just vapor barrier pad.
Absolute worst
no pad no vapor barrier no sealer. Floor will buckle at first summer

In other words if you have an untested pad you are taking a chance. I normally forgo the sealer because of customers wanting to save $$ but don't recommend it.


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## UpComingBuilder (Dec 9, 2008)

What kind of plastic goes on top of the slab?


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## Floorwizard (Dec 5, 2003)

6 mil poly is fine


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## UpComingBuilder (Dec 9, 2008)

So the plastic is called 6 mil poly? Does it come in a big roll like the underlayment does?


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## MinConst (Nov 23, 2004)

UpComingBuilder said:


> So the plastic is called 6 mil poly? Does it come in a big roll like the underlayment does?


Bigger


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## diy'er on LI (Jul 6, 2009)

we're debating doing the exact same project probably next year (we're currently overloaded with ongoing DIY's that need completion before we can put another thing on our plate :huh We dare to dream of a clean basement that we can enter with just socks on.......

question about vapor barrier padding and the 6 mm poly:

what is a good vapor barrier padding (brand? features?)

for the 6mm poly, what should I ask for to get the proper product? Is it called a "6 mm poly underlayment"? or something else?

this website is forever humbling to me... it shows me daily that I know virtually nothing! :whistling2:


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