Concrete Floor Leveler - Should I use it?

[Doug Shepard]

Spent the weekend patching the concrete garage/shop floor in preparation for epoxy painting the floor. Got the worst of the rough areas smoothed out but think the painted floor will still not be real smooth. Is it worth the cost and effort to use some concrete leveler before painting? I looked at some Quick-Krete (sp?) concrete floor leveler that's meant to be put on with a squeegee and be put on as thick as 1/16". Only thing is it will take 7 boxes of the stuff and run around $140 to do it? Anybody used any of this stuff prior to epoxy painting? Is it worth the extra time and cost? Any problems with that thin layer coming up over time?

[Jim O'Dell]

Doug, my first question is does the garage floor slope to the door for drainage? If so, it might take more, and you'd have to build a dam to keep it from exiting the building! I tried some once in a bathroom, different brand leveler. It worked so poorly that I had to chisel it up before I could lay the tile. I ended up using a trowel and some thinset morter to fill in the low spots. Let that dry, then set the tile in thinset as normal. Worked great. But I doubt if that would be a doable thing in a garage/shop. Can you take a picture of what you're trying to smooth out? That might spur a few more ideas from the masses. Jim.

[Doug Shepard]

Thanks Jim
I didnt think to attach pics. After seeing what I shot yesterday morning though I'm not sure they'll help. Took them too early and got some too bright lighting and dark shadows. Looking at the bigger pic with the shop vac, it doesn't look all that bad. But the other pic shows some of the type of problems that had to be patched. Most of those worse areas have now been patched, but the whole floor has a lot of small pockmarks maybe on the order of 1/4" diam.
There is a slope to the floor where it runs to a central drain in the floor but I don't think it slopes to the door at all. To complicate matters I have to do one half of the garage at a time.

Here's the pics but I don't know how much they'll help.

[Lopaka Garcia]

Is this the Quikrete you were talking about? This is a 50lb bag and if you need 7 of these for your garage, then you have a pretty big garage. But you said "box" so I'm thinking you're talking about something else. I couldn't find the specs as far as how much surface each bag covers depending on the thickness of application. I'm thinking at most, you'll only need a couple or few bags of this stuff at minimum thickness.

[Doug Shepard]

Lopaka
I went and checked the one box I bought (and haven't used yet). I think it's the maybe same thing just packaged differently. Mine is in a blue 40 Lb box and says Quikrete Commercial Grade Concrete Resurfacer. The box says that applied to 1/16" with a squeegee that it covers only 35 sq. ft., and less if applied thicker. My garage is 24 x 26 so about 625 sq ft.

[Jim O'Dell]

Doug, from the photos, I see some raised areas as well as some recessed areas around some exposed agregate. (That's not the designer type of exposed agregate. :() I don't know how hard it would be, or the expense involved, but I'd at least consider renting a concrete grinding machine to take care of the raised areas instead of trying to fill everything around it up to that level. I'd do my etching at this point. Then find what would be best for patching the recessed areas, whether it is the leveling compound, thinset, or something different. Thin set might be too soft for this application. Maybe some sort of epoxy filler. Make sure whatever you use will bond with the type of paint/sealer you plan to use as a top coat. Good luck. And if you do grind, make sure to have a really good dust mask. Concrete/cement dust can be nasty stuff. And if at all possible, I'd reconsider trying to do the whole surface at one time. I think your overall results would be worth it. If storing the garage/shop contents for the job to be done is part of your reasoning to do one side at a time, check into how much a PODS unit would run. Jim.

[Allen Bookout]

Doug,

I agree with Jim in that you need to use a product that is compatable with the top coating that you are going to use. Some of the coating companies have their specific make up of repair products. What did you decide to go with? If you went with UCoatIt I know that they have one.

[Norman Hitt]

Doug, there was a pretty good post on this subject within the last year IIRC, and Mark Singer recommended a product for this, but I can't remember what it was, (I could not find it locally in my area though). You might try the search function for that thread, or maybe PM Mark for his input on the subject as he has had experience with this.

[Vaughn McMillan]

Doug, I second Jim's suggestion that you start by grinding the high points down before trying to level the floor surface. I also agree (third?) the suggestion to confirm the patching material you use is compatible with your floor paint. We have a laundry room floor painted with the epoxy paint, and there are some minor cracks and spalled spots that I now wish we'd patched before we painted the floor (strictly for aesthetics).

- Vaughn

[Doug Shepard]

Thanks all

Jim - I think the raised areas you're referring to are some older patches that used hydraulic cement that worked up and loose in some areas. There were also a couple of long cracks that got patched as well as just the flaked off concrete. I don't have any pics yet after the weekend patching, but I think I'm OK and wont need to do the grinding. Any of that loose older patching was busted loose with air chisels, wire brushes (powered & hand), and hammering. Once all the loose stuff was removed and the areas cleaned and vac'ed out, they were patched with Quikrete Vinyl Concrete Patcher. Went through about 7-8 5 Lb batches the first application, and a couple more 5 Lb batches later to put a 2nd layer in the deeper spots. The patches were leveled to the floor by scraping with a brick after they had set up for a while. So the patched areas are looking pretty good. It's the rest of the floor that has me bothered. There are an hundreds of what I'll call pock-marks. Not big enough to warrant using the Concrete Patcher and I'm not even sure how feasible it would be trying to fill those with the thicker patch stuff anyway. But I don't think epoxy paint is going to fill them either ??? Not sure if I should should paint it and be done with it, or put some of the Resurfacer stuff down first.

The paint I'll be using is Sherwin-Williams Shield-Crete
http://www.hcconcrete.com/product/shieldCrete.asp

[Jerry Olexa]

I'm no expert but but keep in mind: you need some slopage for draining and Most important IMHO, be wary of the adhesion. You are applying a different product in your coating to a different product in your base underneath.Will it adhere and not later crack and peel?? I've used some high tech latex type specialty products to smooth out some holes and was basically dissapointed!! Just my experience. G' Luck!

[Steve Clardy]

Once knew a guy that used auto body filler for patching holes in concrete. Sanded down easily. Then he used the epoxy paint on the floor. Worked for him!

[Lopaka Garcia]

Man that's a lot of Bondo!