Help with newly poured concrete floor

[rigldbrg]

Over the last couple of months I've been lurking in the background looking for ideas on how to solve a garage flooring problem. My garage is a typical 24 x 20 2 car garage with a 5'6" x 20 section of that being an 8"elevated bumper that leads into the house. The main portion of the garage floor has become cracked in a few places leading to heaving and unevenness.

I learned about mudjacking on this forum and thought it would be an option to look into. The original idea was to have the floor leveled, cracks repaired, and I would diamond grind the floor and seal with an epoxy product. I got quotes from reliable companies and chose a contractor whose bid would have resulted in a cost of about 1/2 of a total tear out and repour. Since the floor had years of oil, grime, and would have had the cracks repaired with a rubberized product I decided to scrap the epoxy idea and use Racedeck to cover the floor. I also liked the idea of an easier DIY installation.

The contractor mudjacked the floor today and it was a horrible failure. He drilled about 30 holes and pumped a considerable amount of product, but could not get the floor to a point that water would flow out of the garage. His suspicion is that the 5'6" x 20' bumper was added over the original floor which acted like a vice preventing the main floor to elevate. I felt that we came to a reasonable solution and the end result is that he is tearing out the 20 x 20 main section of the floor and pouring new concrete there. The old bumper will stay. Since I am incurring more than I originally budgeted, Racedeck on the entire floor is out. I do still plan to cover the bumper with Racedeck and will now epoxy coat the main floor.

My questions are:
a) how long do I have to let new concrete cure before I can cover in epoxy?
b) I would rather not use a big box type of epoxy; can someone make a suggestion on a quality epoxy/clear-coat that would be suitable for a typical DIYer?
c) Since the epoxy will cover new concrete do I still have to acid wash the surface?
d) How long is a typical epoxy surface coating good for?
e) The contractor will be putting relief joints in the new floor (unlike the old one). Do I have to do anything in these joints to have the epoxy lay correctly, or make the joints invisible?
f) any insight from epoxy veterans that would be helpful is much appreciated.

Thanks in advance for your help! I am always so impressed with how willing people in this forum are to share their knowledge with others.

 

[slickgt1]

Have you considered tile? It won't cost much more than epoxy. My tile cost $1 per square foot. I installed it myself.

Look at my garage renovation link. I had a huge issue with my floor as well. Water was going everywhere inside, and not going out at all. I did a mud-job over my floor, with tile installation at the same time. Couldn't be happier.

 

[Falcon67]

My questions are:
a) how long do I have to let new concrete cure before I can cover in epoxy?
b) I would rather not use a big box type of epoxy; can someone make a suggestion on a quality epoxy/clear-coat that would be suitable for a typical DIYer?
c) Since the epoxy will cover new concrete do I still have to acid wash the surface?
d) How long is a typical epoxy surface coating good for?
e) The contractor will be putting relief joints in the new floor (unlike the old one). Do I have to do anything in these joints to have the epoxy lay correctly, or make the joints invisible?
f) any insight from epoxy veterans that would be helpful is much appreciated.

Thanks in advance for your help! I am always so impressed with how willing people in this forum are to share their knowledge with others.

a - 30 days min
b - I don't do clears on my floors, but a decent product I just used is Kelly-Moore KM-15, considerably less than most products. Not for fancy floors - no chips, etc. It's industrial two part epoxy paint. Comes in dark gray and a light gray
c - yes, it must be given teeth for the epoxy. Etch, grind, etc - something.
d - If the prep is good, long time I'd think.
e - somebody else, I never had a floor sawcut. Backer rod covered with something compatible with the top coat. And I'd think when it flexes, it'll break the epoxy coat and look like ****. I'd just paint and not worry about the saw cuts, personally.
f - some of this all depends on how nice/pretty you want the floor and how you plan to use it. A good two part epoxy with a couple of coats on a lightly used floor would probably look good for many years, even with no clear.

This is my old shop, after move out - 12 years of race car work, welding, etc. It's a gray epoxy, one coat, no clear. The surface is duller than it might be because it had quite a bit of white over spray (in spite of covering the floor) from painting cars. If I had scrubbed it good with something like Simple Green, it'd look pretty good. But we sold the house and they didn't pay for any extra janitorial services.

 

[rigldbrg]

Thanks for the quick reply guys. Slickgt1, your tile job is awesome! I'd be concerned how the tile would stand up to Michigan winters and it seems more labor intensive than the other two options.

Falcon67, I was hoping to get the epoxy down in about a week, but you're confirming what I was hoping to avoid. I was also hoping to avoid etching, but I really do want a long lasting job and agree that prep is the key. I'm going to look into the Kelly-Moore product, but I was really hoping for something with chips and a clear coat. The floor is being poured on Thursday, so I'll post a pic or two of the relief joints and maybe that will be a more descriptive way of determining what, if anything, needs to be done to prep for the epoxy. Btw, Chris, I followed your thread of your new shop build. Very nice!

 

[Falcon67]

Thanks for the complement! You can see on my build thread what I did and that was for a product designed for use on marginal surfaces. Check with any of the vendors that post on here - all have great stuff that will meet your needs. I picked the KM paint because I planned to work hard on it and wasn't really interested in the speckles. I also had an "in" on the commercial side. As noted in the thread, the pour didn't go as well as we'd hoped, so I used a commercial product I thought had the best chance of sticking to just about anything. If it wasn't that, I'd have probably gone with Epoxy Coat. When you decide, that vendor will tell you what prep they would like to make the product perform like you expect. Lots of floors on here done with those products and they all look show quality.