Cement pad for garage

[go iggy]

Hey Everyone,

I need some advice from anyone who knows something about cement. I had a concrete pad put in for my garage 8 days ago and it was 30 degrees out that day. The guy never covered it and it curied to fast. Long story short it has peeled a lot and he didn't finish it well. There are lumps on the surface kinda of like the frosting on a cake. I talked to him about it and he said he will grind it down so it's smooth but is that right? He really dosen't have a lot of experience doing this and stupid me I went for the least expensive price.
Here's the catch we are friends to a certain degree and he does work for me at my job. He's kinda of like a jack of all trades. I don't want to strain the relationship but I want it done right.

Is grinding the right anwser or should I get an expert in before he grinds it down and makes it worse.

Any help would be great.
thanks

[BlackArcher101]

Don't think you really need to cover it anyways, unless it's raining. Covering it would trap in the heat it gives off during the exothermic curing reaction.

[Rhettzky]

Originally Posted by go iggy

Hey Everyone,

I need some advice from anyone who knows something about cement. I had a concrete pad put in for my garage 8 days ago and it was 30 degrees out that day. The guy never covered it and it curied to fast. Long story short it has peeled a lot and he didn't finish it well. There are lumps on the surface kinda of like the frosting on a cake. I talked to him about it and he said he will grind it down so it's smooth but is that right? He really dosen't have a lot of experience doing this and stupid me I went for the least expensive price.
Here's the catch we are friends to a certain degree and he does work for me at my job. He's kinda of like a jack of all trades. I don't want to strain the relationship but I want it done right.

Is grinding the right anwser or should I get an expert in before he grinds it down and makes it worse.

Any help would be great.
thanks

If I were you I'd get a professional in there to check it out. Sounds like your buddy didn't have the proper tools to have the pad floated properly. For sidewalks and stuff it's easy but with a large surface like a garage pad it's really tough to get a nice finish on. Your buddy may have hard feelings but it won't be as bad as the feelings you'd have if he screws it up any more.

[Azure]

Like BA said, you shouldn't have to cover it. The heat is essential for the cemet to cure better.

I'm thinking that however did the finishing didn't do it right, so your best bet would be to get a professional in to fix it.

I don't think there is a reason that cemet should do that, given that it is finished and treated properly.

[ken0042]

I'm no expert, but aren;t you supposed to keep it out of the sun for the first 12 hours or so while it initially sets up; so that it doesn't cure too fast?

[JD]

Concrete may be a little different than my understanding (I deal with oilwell cement for a living), but I would think that the sun could cause the water in the slurry to evaporate, leading to a less than ideal concrete at the surface of the pad. Cement has a specific water requirement for an ideal "set". Whether that would cause peeling or lumps, I don't know, but certainly I would have preferred to keep the sun off.

As for fixing the problem by grinding it, I can't see that being a problem to the cement itself. But it might not look that great!

[Azure]

Originally Posted by ken0042

I'm no expert, but aren;t you supposed to keep it out of the sun for the first 12 hours or so while it initially sets up; so that it doesn't cure too fast?

Could be. I've helped do cemeting in the past, sidewalks and such, and we never covered up the cemet, even if the weather was 30 plus.

Turned out good everytime.

[go iggy]

Thanks for the replies, now the other question is do I make him fix (at his cost) it even if he thinks that its fine just by grinding it?

[IGGYRULES]

Chances are you'll never get it perfect now. The rental store should have a walk behind polisher/grinder (kind of like the big floor polishers that janitors use). Probably will cover a 24"or 36" swath. This should smooth it out pretty good. If it is not up to your standards after that you can get some grey concrete paint (garage floor paint) and that should hide most of the defects. In hot weather when the concrete is hard enough to walk on after you've poured you should prevent it from dehydration by placing burlap sacks on top of it and then running a weeping hose on top, constant watering will work as well, as will laying poly overtop. This will ensure that the concrete will strengthen properly and their will be less chance of cracking. Check out http://www.cement.ca/cement.nsf/e/0D...6?OpenDocument for more info.

[MoneyGuy]

I've done lots of concrete work (it's not "cement," by the way) and I'd call the ready-mix company that provided your concrete. Explain what happened and ask for their advice. It's a free source of good advice. They've seen it all. They may advise you to grind and paint it. Seems to me that should give you a suitable finish. Paint will cover little defects.

Oh, my brother is in this business in Edmonton. If you want, PM me and I'd be happy to ask his advice for you. But I'd call the ready-mix company. They'll know what to do. If you got your concrete from a small outfit, then I'd call one of the biggies and say something like, "Hey, this happened to my concrete.........What do I do now?" Don't tell 'em you bought it elsewhere. Good luck.

[photon]

They just poured my driveway yesterday (FINALLY).. they didn't say anything about keeping it moist or cool though, just not to drive on it for 3 weeks.

Yesterday was cool and today isn't going to be too hot.. tomorrow calls for 25 degrees. That link says 3 days is the basic curing period, and as long as it doesn't go over 27 degrees then it should be no problem right?

I've never seen anyone putting down water on any of the driveways poured in our area...

[Shin Pad]

Well, first off, it's not an good idea to pour concrete in the hot sun. The concrete will hydrate faster and cause shrinkage cracks in the surface. If you used ready-mix concrete, the concrete supplier usually knows what additive to use, and what water-cement ratio to use, to suit the environmental conditions that day. So, they will normally adjust the mix to suit the weather.

The peeling you are describing is a function of curing too fast. I agree with what one other poster said - call the concrete supplier and tell them what happened. I don't care how poorly it was finished, the surface would not peel off if it didn't hydrate too fast. So, inspite of a poor placement job, the batching of the concrete might not have be right.

If you have lumps in the surface (which are not aggregate sticking up), it sounds like it was trowelled initially, and was not done a few more times as the concrete set. You need to trowel it more than just at the initial set. At the initial set, it is still quite pasty, so, you will get the "icing on the cake" look at locations because the concrete is still quite wet. If it was trowelled a few more times, you would have got a much smoother finish.

Anyway, if that is the case, I wouldn't get the same guy to grind down the surface - if he didn't do the trowelling and finishing properly, then I doubt he will be any good at grinding down the concrete.

[MoneyGuy]

If it's too hot, it should be wetted down.