DIY Home Improvement, Remodeling & Repair Forum

DIY Home Improvement, Remodeling & Repair Forum (
-   Bricks, Masonry and Concrete (
-   -   Slab repair (

Speedo 10-17-2007 02:02 PM

Slab repair
Hello. I just had some plumbing work done underneath my home's concrete slab, where they had to break up the concrete, repair the pipes, and re-gravel and finish with concrete. I won't get into my opinion on the quality of their work, but I can say that the new concrete surface does not look smooth and even. There are dips and bubbles that I can't see going away when I put the plywood or laminate floor down.

So my questions are;
1) How level does the underlying concrete need to be to put down flooring?
2) If it is not level enough, what are my options in leveling/smoothing it out?

Thanks in advance!

glennjanie 10-17-2007 09:53 PM

Hey Pete:
In building commercial jobs I have found one phrase that keeps comming up, especially when talking about concrete floors and all ceilings. "water level"
I know, its almost impossible with concrete but one friend of mine said he would 'give a nickel' on the concrete finish; if a nickel laying in a low spot on the concrete was not covered with water, it passed.
The rental store has a gasoline powered concrete grinding machine. It has 2 circular apparatuses with 3 concrete grind stones on each one. It works a little like a buffer or trowelling machine. Keep the stones wet for long wear (they will still cut just as much, but without the dust). Remember, if you wear the stones out you have to replace them before the rental store will take it back.
Laminate flooring is thin and will telegraph any irregurlarity. It may take an hour or two of grinding to make it satisfactory but, believe me you'll be glad you did.

All times are GMT -6. The time now is 08:38 AM.