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New Concrete Floor Over Slab in Basement?

Hi -

Here's what I've got. I've gutted my basement (about 1400sf) and ripped out the old carpeting and padding. What I've found is that the slab is not completely level. It's not bad, but there are some 'low' and 'high' spots no greater than a 16th of an inch.

But, I've also found some vinyl tile that's still stuck to the floor and I believe that there's some absestos in the tile or in the mastic. This tile is not everywhere covering the slab, it probably covers a quarter of the entire area.

I really don't want to deal with the tile, I'd rather just use some type of encapsulation paint on the tile and have someone come in and pour a half-inch concrete floor over what's there, get it nice and level, and decide on floor coverings (carpet, ceramic, etc.).

Has anyone had to deal with something like this or does anyone have any advice? I won't be doing this much before August, so I'll be considering what you have to tell me.

Thanx for your time and if you need more information, please don't hesitate to ask,

Re: New Concrete Floor Over Slab in Basement?

There are companies that do nothing but resurface (grind and polish) concrete. That would take care of both the non-flatness and the possible asbestos. If they grind it wet, there would be no aeration of the asbestos.

Re: New Concrete Floor Over Slab in Basement?

With such a small deviation in the slab, I would tile right over it, encapsulating the asbestos while laying the tiles. As long as the next home owner is made aware, you should be fine. The 1/16" slab hills would make most tile men happy, as opposed to the moon craters we normally see.

Re: New Concrete Floor Over Slab in Basement?

im with the other two, you can go over the existing asbestos tiles,just be sure to have it noted that it is there

as for the floor being out by 1/16th" thats nothing. you can work the morter enough to make things flat. if you were talking 1/2" or greater then id be worried.

ive poured new slabs over existing ones where the old slab was well over 1" out of level. creating a new flat slab for a new finish floor

Re: New Concrete Floor Over Slab in Basement?

All of the above, plus:

Make sure that the tiles you are covering with new thinset are stuck onto the slab and don't move.
And...spreading the thinset correctly, you can overcome an unleveled floor.

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