Concrete House Slab / Carpet Question

Marc1301

Hopefully this fall I am going to get around to replacing my almost 17 year old carpet. Don't get me wrong,......it looks like a lot of folks carpet does after a year or two being as light colored as it is. It is time though, and I want to go berber with a little pattern, and not so close to white. Tired of taking my shoes off for every trip in and out.

I already have about 1500 square feet of tile, and while I like wood floors, I don't like them in my bedroom. I think it would look "funky" to mix 3 different flooring types myself in one house.

Here is the question!
When this was put in, it was simply padding over the slab, followed by the carpet.
I would like to put down a "vapor barrier" of some sort, since for now I live in a very humid climate part of the year. Also in Florida there is no such thing as a mono slab without at least "hairline" cracks throughout.

Am I better off using a liquid type sealer, or just putting down some visqueen plastic under the pad?
When I tiled I used some stuff that you troweled on that was a charcoal grey color. It sealed for moisture, as well as bridging any cracks. Can't remember the name but it worked very well,......I DO remember it was pretty expensive, and it also dried quite fast.

Any ideas would be appreciated.
I am preparing far in advance, as I intend to interior paint at the same time.
Lots of fun coming up![;)]

dcon12

Yes. Don

spasmcreek

around farm country livestock buildings with concrete some use a kind of epoxy finish/sealer that is supposed to be bulletproof...no leak, no acid reaction, moisture, etc...don't know about shifting concrete if it is flexible enuff to not crack....

RtWngExtrmst

I think you're better off to let the concrete "breath" through your carpet. If it lasted 17 years without problem - don't fix it if it ain't broke.

Marc1301

quote:Originally posted by dcon12
Yes. Don

Now I know exactly what to do,......thanks Don!

This is the stuff I used under the tile:
"Mapelastic 315 is a trowel-applied, two-component, flexible, fiber-reinforced waterproofing and crack-isolation membrane. Mapelastic 315 meets ANSI A118.10 requirements for waterproofing and is IAPMO-listed as a shower-pan liner."

I don't have anything major, just typical hairline cracks.

They never used to seal here, but now I am finding they do.
I don't know which is better,........seal it, or let it "breathe" per se.

That's why I'm asking.

Spartacus

there's some stuff called "deamhouse superfoam" that's used as a vapor barrier under laminate wood floors.
it comes in 6 ft wide rolls and a clear 2" wide tape for the seams.
alot easier to put down than thin poly plastics and alot cheaper than the true cement paints (like dry-lok).
I used it when i put in laminate wood florring last year and liked it so much, i used it in the basement under carpet.
lumber liquidators carry's it
just my 2 cents
tom

Marc1301

quote:Originally posted by tplumeri
there's some stuff called "deamhouse superfoam" that's used as a vapor barrier under laminate wood floors.
it comes in 6 ft wide rolls and a clear 2" wide tape for the seams.
alot easier to put down than thin poly plastics and alot cheaper than the true cement paints (like dry-lok).
I used it when i put in laminate wood florring last year and liked it so much, i used it in the basement under carpet.
lumber liquidators carry's it
just my 2 cents
tom

Yes Tom,.......I am familiar with that stuff.
I don't quite understand why they haven't made carpet padding with a sealed back surface that would be somewhat of a vapor barrier and padding all in one.

Visqueen is surely a PIA for something like this.

n/a

Mark, have you considered the floor coating they sell for garages? The paint/epoxy mentioned previously is pretty expensive last I knew. Perhaps the floor coating for garages is cheaper?

mogley98

You do not want a vapor barrier on the "final" side, if you do you will simply trap moisture underneath of it, you don't prevent it. Vapor like heat always moves from a place with more vapor to a place less vaporous. Since you can not get under the slab even sealing it simply limits the passage of vapor from your home into the slab, which should not be an issue, it will not prevent vapor from entering the slab and then condensing BELOW your vapor barrier. So NO do not seal it.

Colt Super

Is it possible that a vapor barrier under carpet is not a good idea ??

I'd go ask a professional carpet sales/installation place, and talk with the owner.

Doug

savage170

Try this place Florida Waterproofing 407-365 4925 they have hundreds of products just tell them what your wanting to do they gave me some stuff to seal some stucco been 10 yrs now and still working great

Maalox

There should have been a vapor barrier installed under the slab when it was installed. If so, you do not need one on the top of the slab also. The condensation will occur on the unconditioned side of the vapor barrier.

We are going to do a similar project in the near future. The wife would like tile or wood in the bedroom, but with tile already in about 1/3 of the house I'm not sure another tile would look good. Wood doesn't apeal to me in a bedroom so we are thinking about going with carpet again also.

The Ultimate Infidel

They actually do make padding with integral barrier. Go to Home Depot and ask to see the upgrade padding. It has a barrier coated on one side to disallow moisture up or liquid seepage down from spills thus allowing near complete extraction. Well well worth the small amount extra. I think it broke down to something like 98 a roll for standard and 136 a roll for the good stuff.

fishkiller41

Use the underlayment that U use w/lamenant flooring. Should do the trick.
Is water/mildew growing under your carpet padding?

SG

I would just put down new padding/carpet and be done with it.If you didnt have a moister problem before then I wouldnt sweat it.No pun intended[:D]

Colt Super

Liar.

Doug

SG

[:D][:X]

mogley98

http://www.buildingscience.com/documents/insights/bsi-003-concrete-floor-problems

Marc1301

quote:Originally posted by mogley98
http://www.buildingscience.com/documents/insights/bsi-003-concrete-floor-problems

Yes,.....my slab was done just like the first pic in your link.
Also I don't have any moisture problems under the padding, as I took a lot of carpet up when I tiled, and saw nothing unusual.

I used that Mapei product because it was highly recommended to avoid cracks in the grout caused by expansion, contraction of the slab on any small cracks in it.

Once again,......there is no such thing as a slab without cracks. At least not in Florida. Mine actually had very few, and they were hairline. You couldn't even slide a piece of paper in them.
In years past we would be roughing in a new home, and you frequently would see cracks everywhere. They stack the block on the slabs while the concrete is still green, and also most builders do not cure the slab properly,.......takes too much time![:0]

I guess I was just thinking it would be of a slight benefit to coat the slab under the pad to help with humidity infiltration.
After reading that link it appears that epoxy would be fine since they use it to help with "wet" slabs, but that is a lot of work and expense for something I guess would not benefit me much, or at all.
Not only that,.......the stuff stinks to high heaven![xx(]

pikeal1

I had some construction done at my house last year and they do, in fact, install a vapor barrier under the slab.

If you put a vapor barrier under the carpet padding, it may creat a situation where you will get mold between the barrier and the concrete slab. I had laminate floors and when I pulled them up, the house stunk like mold for days.