Crumbling garage floor question

[BeachBum2012]

My Uncle is the only other garage guy in my family and pretty much everything I've learned about fixing or making things has come from him. I'd like to help him out a bit by figuring out whats going on with his floor and how we can fix it.

He had a coating put down a few years back and, lets just say it hasn't lasted. Not only is the coating coming up but the concrete under it seems to be crumbling away.

Any thoughts? Top priority is to figure out how to get the floor to stop crumbling. Second would be a new flooring. He likes the idea of a Race Deck like product except for the fact that he does a lot of welding. Any help would be great.

 

[Jack Olsen]

My guess would be the problem wasn't the coating -- but was the quality of the concrete underneath it.

Race Deck would save him the trouble of trying to remove the bad concrete and repair it with a self-leveling layer (or replace it altogether). Fiberglass-type welding blankets are pretty inexpensive. He could get the benefits of Race Deck without too many burn marks if he used blankets when he welds.

 

[BeachBum2012]

My guess would be the problem wasn't the coating -- but was the quality of the concrete underneath it.

Race Deck would save him the trouble of trying to remove the bad concrete and repair it with a self-leveling layer (or replace it altogether). Fiberglass-type welding blankets are pretty inexpensive. He could get the benefits of Race Deck without too many burn marks if he used blankets when he welds.

We were thinking it was the concrete itself. There's about a 10' addition on the back of the garage with newer concrete and it looks fine. He's hoping he can figure something out short of ripping it up and pouring a new slab.

I'll mention the blankets to him and see what he thinks.

Thanks

 

[76 warlock]

I actually sell paint for living and this could be caused by several things. 1.bad batch of concrete. 2. moisture from underneath is getting trapped by the coating and causing the concrete to breakdown. 3. When the coating was applied, the installer may have used hydrochloric acid to etch which actually alters the ph level of concrete. the proper acid to have used should have been phosphoric. Remedy at very least would be to remove all loose material and fill then overlay the floor. however more than likely you will probably have to remove and repour the concrete. If I was you i would have a reputable concrete contractor come out and give his thoughts.

 

[dcs Inc]

Is the garage kept at a constant temp? Or is it heated on a part time basis? I see where some other blow outs were just coated and not repaired before coating.

 

[Edger]

Maybe you should forget about repair, it is too degraded, put all your money into tiles or racedeck type products. It will never be great after topping, not in the long term, so why bother when you will spend heaps on trying to get a good finish that will never last?

I reckon Jack is spot on with his concern about the concrete being the problem causing delamination rather than the coating. A good cover-over product that looks great sounds like the way to go.

 

[BeachBum2012]

Well, its sounding like the consensus may be to replace the concrete itself. Its my Uncle's garage and he has no intentions of ever moving again so it has to last him the rest of his life.

76 warlock - Thanks for the info. My uncle is a contractor and knows a lot about concrete. He was thinking it may be a ph problem in the concrete as well.

dcs Inc - We're in Southern California. The garage is insulated but not heated. Never needed heat out here. The temperature doesn't change enough to really matter much.

Edger - We were hoping to do something along those lines with the stipulation that he'd be able to weld. Looks like this in combination with some welding blankets as Jack suggested may work if it ends up being the route that he wants to go.

Thanks for the ideas and help guys.

 

[blm77]

Had similar problem in basement not sure what it is but the guy cleaned all that mess and pour self leveling concrete on top. We painted with epoxy one room where the storage is - no cracks still rest area under the laminate so not a possibility to check.
Do not know how much you can spend... but only painting doesn't seems a solution.

 

[geologist]

You might try a bag of concrete patching "grout". You'll need to use a grinder of cold chisel to clean up the damaged areas before applying though. My step-dad works on bridges and they use it to fix imperfections in the concrete decking surfaces.

If your concrete is really powdery under the broken areas, you're going to want to replace the slab if possible.

 

[BeachBum2012]

Thanks for the help everyone. Looks like its going to be a new pour.

 

[BECC]

I had the same problem and it was where the concrete finisher dusted in some portland to try and get a better finish since the mud got away from him. You could look into having it ground or shot peened prior for the prep. I hate to cut out concrete.

 

[pop pop]

Most floors don't get the right concrete mix to begin with and fail either from environment or overloading. For a well used garage don't pour the 2000 psi mix. Step up to a 4K or 6K mix and don't add water. You'll get a floor you can use without failing.

 

[BeachBum2012]

Thanks again everyone. That part of the floor was there when he moved in. There have been additions that are holding up just fine. Looks like it was just not done well the first time. Up it comes and its going to get a quality pour this time.