I am preping my concrete slab to lay floating bamboo longstrip. After pulling up the carpet, it seems like the person that put the slab in was drunk.

There are numerous places that the floor isn't near flat. Many are the max of 3/16". Many are 1/4 to 1/2" dips near the walls. It seems like the floor slopes going towards most of the walls. I am thinking I have at least 100sqft to level.

Since the areas are spread out and the room is 32x18, can I use self-leveling compound multiple times. I don't think I can work fast enough to do this in one application.

There aren't any major cracks in the floor so I just think whoever layed the slab did a poor job.

Any hints on putting down a self-leveler would be great. I have read the guide on this site but I am concerned I can't put enough down fast enough in one application.

Any help would be appreciated.

This is from one DIYer to another. I tried SLC last week on my gypcrete floor. The results were less than satisfactory, but that was because I and a friend were trying to do the whole floor, over 400 sf, and we had trouble keeping up with the fast set time of the stuff. You seem to be planning to do spot leveling, which is much easier, since you only have to do one patch at a time. I used Ardex GS-4. Follow the instructions for whatever brand you use. Here are some things I'd recommend, based on my experience:

1) You may need to prime the surface you are leveling.
2) Get someone to help you pour and mix it.
3) A 5-gallon paint bucket will hold one 50-lb bag mix. Any more than that and you need a wheelbarrow or bigger container. If you re-use a bucket, make sure to clean it out thoroughly before adding another mix.
4) Use a paddle on a heavy duty electric drill to mix. You can't do it by hand.
5) Add cement to water, not the other way around.
6) Make sure you mix it thoroughly so that it's consistent, scraping excess off the sides and bottom of the bucket using a stick. Try not to incorporate too much air while you're doing this, though, because this can cause pin-holes in the cement.
7) I used a rake to pour it out, but you could probably just trowel it around if it's a small area. Don't poke at it too much, though. They don't call it SLC for nothing.
8 ) Let it set up a bit before screeding it and/or feathering the edges with a trowel.

Ok, after more inspection, I have a 2' x 5' hump in the floor. Over an 8' length, it can throw the flatness off by an entire inch.

I think I need to get this grinded down. I have an angle grinder but I think that would be suicide to try and use.

How much would a contractor charge to come out and grind down a hump in my slab? I live in SC if that helps people give a rough estimate.

thanks,
Jim

Use the patch method. Trying to use a SLC can get you into trouble real fast.

I thought that grinding down a slab was not a DIY project but I recently saw a homeowner do it on Hometime and as I recall they made it look real easy (they make everything look easy though, don't they). Unfortunately I can't for the life of me remember what tool they used (I think it was something made for that purpose) Perhaps it will come to me but you may want to go to a good rental yard. I have found that the ones that rent to pros really know there stuff.

I tend to know my limits

I do not feel comfortable grinding down my slab. I would definately rather have a professional do that for me.

You may not be able to find anyone, I tried and could not. Typically contractors do not want to do partial jobs especially if the homeowner is doing some of the work. For example, at lot of people want a tile guy to put in the shower pan (which is the hard part) and then the homeowner does the tile. No reputable tile man will do this for fear of being sued later for leaks- can't really blame them.

Although I have not done it, grinding the slab cannot require any more skill than patching it. The only thing that can really go wrong is that you grind a little too far or it takes too long because of using too small of a machine. The former doesn't matter because I know you have to do some patching anyhow. You should try renting a large angle grinder with a diamond ginding wheel and see how it goes. The biggest problem is dust. I highly recommend you build a small shelter out of clear plastic sheeting around your work area or you will be cleaning concrete dust for months.

Whatever you decide, good luck.