Vapor Barrier ?

[nonhog]

Any reason not to put plastic down befor a pour ? My salesman said they don't use barriers with reinforced concrete ? sounds funny to me .
any input ? thanks in advance !
I added crushed 5/8 rock on top of the fill FWIW

 

[5wndwcpe]

The reason ? Save a few bucks and some extra work. Then, later on, when your epoxy floor peels off in sheets, you can call your salesman back to pick up the slab and hold it while you sneak a vapor barrier in underneath.

 

[Franz©]

Salesman- (N) a no good sonofabych who will tell any lie that he can remember to get the sucker to sign on the bottom line. Some are known to be aflicted with Herb Tarlock disease, but most are just completely amoral.

Put the damn plastic down, it ain't just a vapor barrier, it eliminates the water being wicked out of the concrete during the pour and makes a better finished product.

 

[Steve in Mi]

Any reason not to put plastic down befor a pour ?

None, no good reason that I can think of. Does your contractor work for you or do you work for him - the one in charge should insist on the poly.

 

[SC-Eric]

I think it's crazy not to use the barrier. If you are planning to epoxy the floor... you can save hours of prep later (acid etching, blasting, grinding, etc.) by applying BondTite 1501 as the curing sealer. This will act as the primer for the epoxy and will completely eliminate any prep other than sweeping and mopping! The 1501 MUST be applied to the pour within 24 hours but preferrably as soon as you can walk on it. If you were going to use a curing sealer anyway to help promote hydration this is a no-brainer.

 

[dawg]

gee and I thought I got ripped by installing 2 layers of vapor barrier and extra reed bar!

 

[bmwpower]

The one "bad" thing about vapor barriers is that they keep the slab from drying out too quickly. In cold weather, this could be a bad thing if you're in need of getting the slab to cure up in order to finish the surface ASAP. But this is usually taken care of by adding calcium or other additives to accelerate initial setting-up.

Other than that and possibly the cost being a factor (if you're really strapped for cash), you should always add one.

 

[IDASHO]

If you are THAT strapped for cash, then you probably shouldnt be building a garage/shop I put a layer of 6mil vapor barrier under my slab. Cost me all of $60 or so.

 

[JohnZ]

Knowing what moisture migration will do to ANY floor coating, I put down a 10-mil poly moisture barrier, then laid 5/8"-thick 4' x 8' sheets of high-density closed-cell foam with heavy foil on both sides on top of that before pouring the 2600 sq. ft. slab. Then had it steel shot-blasted 3 months later and epoxied. That was seven years ago, and not one molecule of moisture has migrated through the floor!

You can't fix it after the slab is poured; do it now or forget about having any kind of coating ever stick to the floor.

 

[nonhog]

The more I study on this the more it make sence , however I keep hearing about curling and cracking , doesn't seem like thats been an issue for anybody here . Wolverine mentioned bondtite curing sealer ? Looks like I have more studying to do .

 

[Hammerdown]

Always use a vapor barrier.

Your salesman indicated that they don't use a vapor barrier in combination with reinforcements? I would ask for a detailed explanation on this one, as I have never heard that. The re-bar would make the concrete stronger, but that is still no reason not to use a vapor barrier.
Let us know what he says please.
If you are going to use an epoxy or similar floor coating, you should do a lot of homework on which product will best suit your needs before purchasing one.

 

[nonhog]

salesguy said can't use fiber reinforcement with a Vapor barrier . As of now I plan on putting down my Vapor barrier myself and use wire reinforcement.
Of course my contractor wants more money for labor
Thats after I install everything , cause they'll have to lift the wire into place
which is true and will take a lil more time and for sure some effort . 625$ can you believe that . I told him NO WAY he has yet to get back to me .
They say the fiber would come to the surface with a Vapor barrier , which I could see to a small degree . I wonder if it would be worth it to chance that ?
1200 sq.ft. of concrete 100 $ or less in extra labor but what do I know ?
He keeps forgeting I was a concrete grunt 20+ years ago . so I know just enough to be dangerous Course I may have forgot alot ?

 

[PurdueSD]

Time to look for a new sub contractor...nuff said.

 

[nonhog]

Time to look for a new sub contractor...nuff said.

Just not that easy . I am happy with the build quality its just I have a contract with them which I could fire them but would they adj. prices fairly or would that screw me even worse ? So I will stand up to them and get it done and over w/o letting them walk all over me . Unless they really piss me off I'll stay the course . At least I know what I have to deal with .
They are not getting more than is reasonable from this working class guy . I understand if they dont make a profit they can't keep the lights on . All I insist on is fair and resonable .The Co. is 95 % done except for Garage doors and concrete .

 

[xrayman]

Use the vapor barrier. Fiber in the concrete will come to the surface regardless of what you do. Skip the wire mesh and use rebar tied and crossed to make 2 foot sqaures. Easy to pour with if you buy the cheap plastic chairs to set it on and it will not end up in the bottom of your concrete like the wire mesh will.