Floor Problem

[Steve Calvin]

We bought this house about 6 years ago. I don't know what's up with the garage floor, whether they used the wrong mix in the cement or what but it has a serious "pitting" problem. I'm talking it'll hurt your feet if you walk on it barefooted. I've been told that if I just add a surface layer that it will crack and crumble off.

Anyone know of somthing that I could fill it in with that would hold up? I'm in the NE US where extreme winter conditions are definately a factor. I can post pics if anyone wants to actually see the condition.

 

[JonM]

If its just pitted and not loose, you could rent a concrete grinder and smooth it out.

Then you may want to put down an epoxy floor coating. If its loose, you have to remove the concrete down to where it is stable. Then you would have to spray it with concrete surface prep to help the new concrete bond to the old stuff.

Pics can be stored and shown on this site...look below when you are posting you will see an "MANAGE ATTACHMENTS" button

 

[Steve Calvin]

Thanks Jon. This sucker isn't just peeling, it's seriously pitted. I'm talking maybe 3/8"-1/2" deep in some places. Who ever did the job didn't have a freekin' clue what they were doing.

I'll take some pics tomorrow and get 'em up tomorrow night or Friday so you can see it. I don't think that a grinder's gonna do the job, but I could be wrong.

Thanks for the reply.

 

[Steve Calvin]

It tough to get a good picture that shows the condition. Hopefully this will suffice. The "craters" that you see are about 3/8" deep or so.

 

[MMM]

I am not an expert in concrete, but what you are seeing is often the result of the concrete freezing before it had a chance to set. If the concrete is poured when the temperature is forecast to go below freezing it must be protected from the freezing temperatures during the initial cure period or at least until the water either evaporates or is driven off by the heat of the curing reaction. If the top layer of the concete contains too much moisture and it freezes, it the water expands and fractures the top layer from the main substate. As the floor sees use, the top layer begins to crumble. And depending on how deep the frozen layer was, it could continue to crumble past where it is now. Take a light hammer and hit it softly in a few places and see how easily it crumbles.
There are a number of methods and materials available to repair situations like this, however nothing will last until all of the weakened concrete is removed, the base material must be solid. I think you need to get somebody who knows what to look for to examine the situation and help develop repair or replace options.

Mike

 

[JonM]

It looks like they didn't even attempt to finish the slab...Anyway, if you don't think grinding it would help, then my next suggestion would be to rent a jack hammer (you could even rent an electric pavement buster) and have at it for the weekend about 100 bucks...It will give you a good workout. The biggest problem is getting rid of the old stuff. You could rent a dumpster (12 yarder) 450 bucks. The old slab is most likely (normally) only 4 inches thick, so once you get one corner busted out it should go pretty quick. I don't know how big your garage is, but to know how much concrete you would need you measure the width times the length times .33 and then divide that by 27. Example 24' x 20' x .33 = 158.4 divided by 27 = about 6 yards. ready-mix is usually about 75 dollars a yard these days. Look in the paper for a cement finisher to help you finish it.

PS...don't forget the 6x6 wire mesh to make the slab stronger, you can get it at home depot or lowes for about 60 dollars

 

[Steve Calvin]

Thanks. You two have pretty much confirmed what I was afraid of. I've looked into having the garage taken down and a new two car put up. At twenty-five grand, that's not an option and I'm no builder. (great gopher though. )

As for jack-hammering and re-pouring, I could do that but the current concrete goes under the walls and I wouldn't be able to hammer that out. Wouldn't it be a problem getting it to get a good bond with that?

 

[corvettecrazy]

When I lived in Wisconsin our neighbors floor looked like that. His floor was poured properly, in the summer. He talked with a few people, and they all said it was most likely due to the salt and chemicals that are used during the winter. Then they sit on the cement and eat away at it. IDK what they put on roads near you but that could be a possibility also.

 

[JonM]

As for jack-hammering and re-pouring, I could do that but the current concrete goes under the walls and I wouldn't be able to hammer that out. Wouldn't it be a problem getting it to get a good bond with that?

Not at all...its done all the time...depending on the soil and it must be compacted...you may want to drill into the old concrete that goes under the wall and slide in some half inch by 12 inch rebar..about every 16 inches on center would be fine and about 4 inches deep. But if your soil is firm their is no need for it.

 

[Steve Calvin]

ok thanks. I think that next summers project is now "on the books".

Hm... maybe I'll have a "jack hammer" party. Serve Mint Julips (made with Jack Daniels) through a port but and some racks of ribs on the smoker along with a 1/2 on tap.

 

[hAZcAT]

You can pour a 3 inch slab on to of the current slab, if you can afford to lose the head room, save ripping it out, or put Racedeck down www.racedeck.com a few hundred bucks and you can have a nice floor.

 

[vethead]

If you decide to tear out the old concrete, one option might be to check with the local concrete yard and see if they will take the old stuff from you cheaply. The yard around here charges anywhere from free to $3 a load to dump it, just depends on their mood. You must do it yourself, but it cost about $12 last time I used them. Just an idea. Also, an easy way to figure out how much concrete you need is to take the entire square footage, and divide by 80. Works the same, and is less math. Less chance of messing up the calculations. Both formulas work though.

 

[surferdave]

If you went back to fix the concrete job it would probably be an expensive fix. Just a thought, but did you ever think about tile? Morter would fill in and level and support a durable tile floor. Just a thought.

dave