My New Concrete...HELP!!!!

[Kristang]

I had my slab poured over 2 months ago and it has NOT been sealed. The past few days these blisters have been popping up all over the floor. I've done some internet investigating, I've talked to my contractor and a couple of others. From what they are telling me, it is water that was trapped in the concrete and it's now surfacing. I wanted to talk to the experts here and get your input and suggestions. Is there any concern with structural integrity? I am putting 2 post lift on this pad. I know the contractor will have to address it but I'd like to know what my options are? Cut out and replace the area the lift will be mounted, grind the floor and coat it, or cut the whole thing out and replace it?

 

[readhead]

Looks like it may have been overworked and the spalling is about to begin. Let us know what the contractor says.

 

[930dreamer]

Is this an entire shop floor? How big is the pad? That looks like trouble.

 

[Kristang]

Is this an entire shop floor? How big is the pad? That looks like trouble.

26 x 28 and yes, they are all over the surface. More concentrated in some areas than others. I feel nauseated. LOL

 

[ConCretin]

It's not water currently rising to the surface - it's water that rose to the surface while the concrete was initially setting. It's called blistering and is caused by sealing up the surface with steel trowels before bleed water subsided. It's not a structural issue but the blisters will continue to break leaving an ugly surface that is very difficult to successfully repair.

This is the 100% the finishers responsibility and was 100% preventable.

 

[Kristang]

It's not water currently rising to the surface - it's water that rose to the surface while the concrete was initially setting. It's called blistering and is caused by sealing up the surface with steel trowels before bleed water subsided. It's not a structural issue but the blisters will continue to break leaving an ugly surface that is very difficult to successfully repair.

This is the 100% the finishers responsibility and was 100% preventable.

What would you do if you were me in this situation? Will grinding and epoxy remedy the situation or will it continue to do this or do I go as far as cutting it out and replacing it? Has the concrete lost any of it's strength due to this?

 

[madcitym]

What would you do if you were me in this situation? Will grinding and epoxy remedy the situation or will it continue to do this or do I go as far as cutting it out and replacing it? Has the concrete lost any of it's strength due to this?

I would make the contractor pay for an acceptable coating. It is not a structural issue at all but as others have said, it is poor workmanship and borderline incompetence as dealing with bleed water is concrete finishing 101. The surface will continue to get worse and flake away. As others said, the blistering is bleed water that rose above the surface, for every blister that is sticking up there is more that are not and the surface will eventual delaminate.

I would not trust this contractor to tear out the slab and pour a new one. Bring in a reputable coating contractor and have your concrete guy foot the bill.

 

[ConCretin]

What would you do if you were me in this situation? Will grinding and epoxy remedy the situation or will it continue to do this or do I go as far as cutting it out and replacing it? Has the concrete lost any of it's strength due to this?

While blistering can be associated with high slumps (i.e. lower strengths), I'd be primarily concerned with the surface at this point. The only solution is to remove the de-laminated surface concrete and repair the damage.

Grinding and patching would restore the surface but probably wouldn't look great. Obviously an epoxy or similar product would improve the appearance. As long as you find and remove all the blisters, and do the repairs properly, the solution should be as permanent as the coating.

I think you have a legitimate claim against your contractor. As I mentioned, blisters are entirely preventable and avoided with proper finishing. I'd start by demanding removal and replacement and settle for repairs as described if you are willing. Hopefully your finisher is a stand up guy. Good luck!

 

[Kristang]

While blistering can be associated with high slumps (i.e. lower strengths), I'd be primarily concerned with the surface at this point. The only solution is to remove the de-laminated surface concrete and repair the damage.

Grinding and patching would restore the surface but probably wouldn't look great. Obviously an epoxy or similar product would improve the appearance. As long as you find and remove all the blisters, and do the repairs properly, the solution should be as permanent as the coating.

I think you have a legitimate claim against your contractor. As I mentioned, blisters are entirely preventable and avoided with proper finishing. I'd start by demanding removal and replacement and settle for repairs as described if you are willing. Hopefully your finisher is a stand up guy. Good luck!

Thank you!!

 

[Kristang]

While blistering can be associated with high slumps (i.e. lower strengths), I'd be primarily concerned with the surface at this point. The only solution is to remove the de-laminated surface concrete and repair the damage.

Grinding and patching would restore the surface but probably wouldn't look great. Obviously an epoxy or similar product would improve the appearance. As long as you find and remove all the blisters, and do the repairs properly, the solution should be as permanent as the coating.

I think you have a legitimate claim against your contractor. As I mentioned, blisters are entirely preventable and avoided with proper finishing. I'd start by demanding removal and replacement and settle for repairs as described if you are willing. Hopefully your finisher is a stand up guy. Good luck!

One more question. I am installing a 9000 lb. 2 post lift in this garage. If I were to agree with surface repairs, ending in either epoxy or a modular floor covering, should I request the area of the concrete the lift will be attached to be replaced or do you feel the integrity of concrete has not been compromised enough to warrant that?

 

[Glory]

The integrity or structural soundness is not a concern with blistering. I would not accept a refinish on that slab. I would have them replace the slab, not because it will fail but because you didn’t get what you paid for.

Grinding would be the only way to cut that surface enough and that still may not be enough...

There are industry standards, look into them and it will give you the basis for a claim in court.

Oh.. I also wanted to add that I am very sorry this happened to you. I know that feeling

 

[Retroman]

Was your contractor licensed? If so you may need to contact the contractors board if he will not repair and warranty the work to your satisfaction. That's a shame and I feel for you.

 

[Miss the Pontiacs]

My buddy had a crappy pour. The concrete supplier was willing to remove and replace. But due to the slab having a thickened edge and in floor heat tubing my buddy was unwilling to go this route.
What contractor did for him was grind it down and place a Polyaspartic floor for no cost. It is now close to 10 years old and looks great. I was over the other day and took a couple of pics as I am looking at the same flooring for my garage.
So yes there is life after a problem pour.

 

[ConCretin]

One more question. I am installing a 9000 lb. 2 post lift in this garage. If I were to agree with surface repairs, ending in either epoxy or a modular floor covering, should I request the area of the concrete the lift will be attached to be replaced or do you feel the integrity of concrete has not been compromised enough to warrant that?

The presence of blisters alone doesn't call the structural integrity of the floor into question. Surface defects can be caused by excessive slumps i.e. too much water, which will reduce compressive strength. There's just no way be 100% sure without additional information but I don't see any reason for concern based on what we do know.

With a lift, I'd be primarily concerned that the thickness and compressive strength of the slab meet the lift manufacturers requirements. Thickness is easy to verify by drilling and if you question the latter, you could have a testing lab take and break some cores.

 

[Kristang]

Thank you for your wisdom and suggestions. Not something I wanted to have to deal with, especially with winter coming soon and I'm trying to get this building buttoned up so I can use it. I guess I'm going to learn some new things!

 

[LegacyIndustrial]

Drag a chain along the surface, listen for the hollow sound of the blister.
Crack it open with a ball-peen hammer or similar.

Fill with this: https://www.legacyindustrial.net/products/concrete-repair/hd-110-epoxy-concrete-patch.html

or similar.

Once all the voids are filled well, have to grind the surface and then choose a high-hide system like FullFlake.

Good luck.

 

[ConCretin]

Drag a chain along the surface, listen for the hollow sound of the blister

Legacy, you probably have more experience than I do in this area but I've found that the chain drag method works well for traditional de-laminated areas that tend to be larger. Blisters tend to be smaller 1" to 3" and are thus harder to find with a chain. Fortunately blisters can usually be seen with the naked eye especially with a low angle light.

 

[Kristang]

Legacy, you probably have more experience than I do in this area but I've found that the chain drag method works well for traditional de-laminated areas that tend to be larger. Blisters tend to be smaller 1" to 3" and are thus harder to find with a chain. Fortunately blisters can usually be seen with the naked eye especially with a low angle light.

I can definitely see them and pop them with a hammer! Contractor is coming on Monday to inspect the issue. Im tempted to pop them all, LOL

 

[LegacyIndustrial]

Legacy, you probably have more experience than I do in this area but I've found that the chain drag method works well for traditional de-laminated areas that tend to be larger. Blisters tend to be smaller 1" to 3" and are thus harder to find with a chain. Fortunately blisters can usually be seen with the naked eye especially with a low angle light.

We had a gjmember try it with success years ago. He had quite a time filling all those small roundish holes. I agree it’s better with delams but worth a shot.






Sent from my iPhone using Garage Journal

 

[Kristang]

Contractor came out today. First thing he said is he can offer me a $500.00 refund for the trouble. This is after he told me he has never experienced this before and knows nothing about it. I told him this is not what I paid for and if it's a product issue, he didn't get what he paid for either. I told him I don't care who's fault it is but this needs to be made right for me. He's going to talk to his concrete vendor and get back to me early in the week. We went around the garage and lightly tapped on the blisters with a hammer and they break open with little effort. This is not going to be fun.

 

[jhelrey]

Located near you. Good luck

 

[SGKent]

not to be negative but document ever conversation well in case you have to go to court, including putting down legitimately what was in all your prior conversations with him. Look at the contract carefully. What may happen is suddenly your calls go unanswered.

 

[ConCretin]

Contractor came out today. First thing he said is he can offer me a $500.00 refund for the trouble. This is after he told me he has never experienced this before and knows nothing about it. I told him this is not what I paid for and if it's a product issue, he didn't get what he paid for either. I told him I don't care who's fault it is but this needs to be made right for me. He's going to talk to his concrete vendor and get back to me early in the week. We went around the garage and lightly tapped on the blisters with a hammer and they break open with little effort. This is not going to be fun.

It'll be interesting to hear what his concrete supplier has to say but I doubt it will be helpful. This is not a material problem - it is an installation problem. The only material related issue I can think of is if the concrete was air entrained. Air entrained concrete should generally not be used for interior, steel troweled floor slabs because it can lead to de-lamination and blisters.

Might be a good idea to call the supplier yourself and ask what the mix was. While you've got them, it might also want to ask if they have been paid. If a conflict develops, you'll want to know their payment status. Not sure if you still owe the contractor any money but you'll need to make sure they were paid or you could add insult to injury with a lien on your property.

Blisters can be a little complicated. There are a myriad of variables related to mix design, weather, sub grade and finishing procedures that cause them and occasionally even good finishers get them. At the end of the day however, the finisher is responsible. If I got a call that a slab we placed had blistered, I'd send the saw cutting crew down the next day.

Sorry to be so negative but I want you to have all the information possible. Feel free to Pm me if you'd like to talk any of this though.

 

[The Wolff]

I just got done going through a bad topcoat finish. Mine was dusting and showing areas of small crumbling. The concrete contractor totally blew me off and blamed the concrete company when it was really his fault. To make a long story short, I hired another guy who ground it down and flooded it with densifier to harden the top surface. He then epoxied the floor. His epoxy work was bad but it is at least better than I started with albeit VERY expensive.

If I had your floor (or mine again)....i would break all your "blisters", vacuum and pressure wash, coat it heavily with a densifier for hardness and then cover it with Racedeck, Swisstrax or a similar snap together tile. I would put together the estimate and get what you can from your contractor.

Sorry to hear of your issues---I know how you feel.

 

[Kristang]

Thanks again gents! I have documented everything and I paid them upon completion of the job. I was told when the truck arrived it had traveled from a long distance and they needed to get it down quick and troweled. The contractor told me yesterday they had to add water to it when it arrived. It's going to be interesting to see how they handle this because he was sure the concrete company would point the finger at installation. They are a third generation family company, a friend of a friend and I have referred a bunch of new work to them through my employer. Not that is matters but I'll find out what kind of people they are! If I can determine the integrity of the concrete has not been compromised I would be good with what The Wolff suggested. Although I did tell him if they don't cut it out and replace it I at least want the area my 2 post will be attached to replaced. I'm not offering the grind and epoxy at this point, I'm waiting for them to respond.

 

[Snip]

Any further updates on if or how this was resolved?

 

[Armorpoxy]

Sorry you are having these issues. Since the experts seem to think this is more of a cosmetic issue rather than a structural issue, a simple solution would be to just cover over the floor with our solid www.supratile.com interlocking tiles. We sell these frequently when encountering spalled/bad concrete.

Get your contractor to pay for them and the floor will last for 50 years or more, plus you will have a gorgeous floor in one day.

Certainly the tiles will be less money than ripping up the floor and replacing it, and then having to coat it.

 

[Stellaontap]

Also....if the contractor added water to the mix at the time of placement which changes the whole mix design would also change the compressive strength. And if water was added and the slab was over finished then there could be segregation of the mix. The supplier of the concrete may document the amount of additional water added by the contractor to cover his end. If you think the concrete may have structural issues have them drill a core for testing.

 

[BigGarage]

Thanks again gents! I have documented everything and I paid them upon completion of the job. I was told when the truck arrived it had traveled from a long distance and they needed to get it down quick and troweled. The contractor told me yesterday they had to add water to it when it arrived. It's going to be interesting to see how they handle this because he was sure the concrete company would point the finger at installation.

If the contractor added water then they changed the mix the company sent out. This could definitely change the strength of your floor. As someone mentioned, this floor should be completely replaced because it's not what you paid for.

Dennis