Ask Me Help Desk - Can you lay concrete over concrete safely

My pack patio has some cracks in it. A couple of them are hairline and one is about an 1/8 of an inch and it appears to go all the way through. I was curious if a good fix might be for a concrete contractor to come out, place forms around it, and lay about 1/4 inch new concrete on it.

I have a step down to the patio so this would not be a problem and thought the new concrete would fill the current small crack as it poured. Is this a possible solution as at times water creeps onto my porch so thought this might solve two problems at once. So this is more than just a cosmetic fix here, but the cracks do look bad.

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Is this a possible solution as at times water creeps onto my porch so thought this might solve two problems at once. So this is more than just a cosmetic fix here, but the cracks do look bad.

If the water creeps onto the porch now and its leaning towards the house then that slab is done at this point. It will only lean more later especially if it freezes there.

1/4 concrete is not concrete because the stone in concrete it bigger than that. A topping of the patio is one way of surfacing the old top but won't stop a crack. Filling in the crack with concrete caulk is one cheap way and ugly.

The myth about concrete and cracks is cracks never go away. You can fill them but sooner or later they come back. All Crete moves at one time or another just from temp changes.

You never want water to seep onto the concrete porch. The pour is to low and or it moved and sunk at the wrong end. Also there should be 4" clean crushed stone ( 2b) under the slab to begin with.

The only real fix is tear out and start over, add wire Mats in it or rebar on new pour. There is a lot of products like "Throseal" and "Master builders" products to resurface the Crete but it not a lateral structural product. Crack will come back.

Pouring Crete for 30 years and this question always comes up on job calls. I have a motto for that. " When in doubt Tear it our" Just throwing money and time on a ' I hope it works" Not to mention how ugly top coating looks.

My patio is 10x25 and is about 10 months old (so is the house). The water I've noticed is only from poor grading of the lot and have some ideas to fix it. I am not sure what the builder will do with these cracks. When I asked them about putting rebar in before the build I was told it would not help in cracking only large issues. I have to wonder if the rebar would have avoided these issues I see now.

I think three cracks going down the 10' section (all the same direction) is too much. This is from the back of the house to the yard.. not from side to side. I have to wonder why they didn't use expansion joints or something on such a large patio. In your experience would you have recommended expansion joints and rebar. I know hind site is 20/20, but better to learn from these things now.

For a perfect build and lets remember its about cost. I have very good success with rebar and expansion joints. I'm not sure of your Geo here.

A perfect set up first to to mechanically tamp the dirt before the stone. That should NOT be tamped flat. I slope my tamped ground away from the house on the get go. Then I use 2b clean stone and it takes a tad more because of dirt slope is more then 1/4 per lineal foot of the correct concrete slope.

Depending on the size of the patio I use Felt expansion and rebar through the felt and in the rest of the pad. What that does is allow the Concrete to expand and contract move vertically with the expansion joint there and yet the adjacent pads rise and fall in since with each other and not create a stumble area.

The other option is using pool vinyl expansion or treated 2/4s.

Another way is 1/2 bar and another 1" of Crete and make the pad strong enough to become a solid unit in itself.

Either or you should have had 2 groves in your pad to begin with bar or not. IE 2 cracks at the 10 wide areas. Every wonder why a city walk holds up longer... Its regulated for expansions and grooving. Patios are not.

I live in one of the toughest areas for crete. It gets to 25 to 0 in the winter and a very damp Geo and 95 to 100 in the summer. That is one of the harshest environment Crete can be in.

I had discussed the cost with my builder, but they told me it would not matter what I did "concrete will crack" so it was not work the investment of other items. I live in the midwest with moderate temps and so the weather is not that extreme, but it can range. Here's the kicker.. I've recently looked at other houses they have build and noticed on some porches they did the expansion joints.. I know the builder will not want to tear it all out and fix as that is $$$ out of their pocket, but my fear is after the year warranty the crack will just get bigger and bigger over time. Thanks for all feedback.. it has been VERY helpful.

Last two quick questions.. worst case scenatio.. they only cosmetically fix the cracks with the items you have mentioned. Should they also add the expansion joints? I have already painted and sealed the patio before it cracked so it will look even worse. I can go back and repaint and seal the patio and maybe it would look okay again since I'd paint over the fixed areas? I used a Sherman williams product and sealer that looked really nice, but these cracks just take away from it alll now.

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they told me it would not matter what I did "concrete will crack" so it was not work the investment of other items. I ...

He is blowing smoke at this point and using the "crutch" that all Crete cracks. Many do but not all. The simple game in logic here is assume it will want to crack and how are we going to control that future crack. I will NOT give one year , 100% guarantees on out side flat work If my recommendations are not followed. BUT I educate the customer on the options and the cost diff along with the best application to use on that project. If that create cracked in less than a year and mod temps I would be chasing him down the road. I NEVER had that happen on a small patio such as yours.

Your ground most likely was never mechanically tamped. Bo Bo already on new house being built already. I even mechanically tamp the stone on patios. I, also the Hoe man that digs it out. On yours I would have also given an option of putting below grade footers and block walls in case you may want to put an addition on the house in many years to come. Another example of giving all the options for the customer.

I would chase him no matter what.