How long can I wait after grinding before laying down polyurea?

[drx2]

Planning on putting in a polyurea floor in the garage. It is approximately 700 sq ft, and will be new, clean concrete floor. Wanted to do the project in stages. First grinding the floor, then the polyurea. Can I wait a month or 2 after grinding to the coat the floor? The house will be empty, and the garage unused.

Any other prep I should do? I was planning on vacuuming it again prior to coating.

Thanks in advance

 

[Shea]

Planning on putting in a polyurea floor in the garage. It is approximately 700 sq ft, and will be new, clean concrete floor. Wanted to do the project in stages. First grinding the floor, then the polyurea. Can I wait a month or 2 after grinding to the coat the floor? The house will be empty, and the garage unused.

Any other prep I should do? I was planning on vacuuming it again prior to coating.

Thanks in advance

What you have planned is fine. Nothing will change. Just keep it clean.

 

[BlindViper]

Why are you grinding new concrete?

 

[JoeMcGov]

Why are you grinding new concrete?

He's likely got a trowel finish and is just "opening up" the surface of the concrete to provide an appropriate surface for proper adhesion.

Some prefer to do a light sandblast like surface preparation.

The polyurea manufacturer will tell you how to properly prepare the surface. Or describe a properly prepared surface.

 

[drx2]

Exactly. A very smooth troweled surface.

 

[BlindViper]

Exactly. A very smooth troweled surface.

I was just curious I was told to just etch my concrete.

 

[drx2]

I think it would be easier to grind it than deal with acid and water going all over the place, worrying about it getting on the lawn and plants, etc. I'll let you know after if I made the right decision. Plus I think it would prep the surface a little better.

 

[Armorpoxy]

Agree with Shea, keep it clean or re-vacuum before applying, it should be fine.

 

[benwah]

Why are you grinding new concrete?

The new concrete needs to be opened up to accept coatings. Doesn't matter if it is brand new or 25 years old, the concrete needs to be profiled. Plus you achieve a better Concrete Surface Profile with a grinding than acid etch.

 

[LegacyIndustrial]

Agree with Benwah. However, a good etch is ALWAYS better than a poorly executed grind.
Therefore, on new floors only, we are good with an etch, done properly.

Good luck!

 

[dcg9381]

I think it would be easier to grind it than deal with acid and water going all over the place, worrying about it getting on the lawn and plants, etc. I'll let you know after if I made the right decision.

After renting a "wet" grinder from Home Depot, I can assure you that there isn't much that is easy about it... You're gonna use muscles you didn't know you had!

OP, I'd say you're clear to coat it as soon as it is totally dry (if wet ground) or as soon as you have dust off. IMHO, grinding isn't necessary for concrete in decent shape with polyurea...

 

[Armorpoxy]

100% agree with Benwah, all concrete needs prep of some type even if new.

 

[benwah]

IMHO, grinding isn't necessary for concrete in decent shape with polyurea...

Disagree. Sorry but it is incorrect to say that polyuea magically adheres to concrete without surface preparation. If anything you need even better prep with polyurea because of how fast it cures compared to epoxy.

If you want a successful floor, you must properly prepare a concrete surface. There are industry standards that we must follow to ensure proper installation and adhesion. Don't do shortcuts or you'll have a bad time.

That being said, I have no clue what product you are using, or what the manufacturer recommends. Doesn't matter much though, something still needs to be done.

For example I just fixed a 1700 SF interior slab that failed because the GC didn't do any surface prep other than a mop with TSP. Failed in 5 months.

You have no idea if any curing agents, or other weird **** were truly added to the mix, which could act as a barrier or "sealer" and not allow the concrete to accept coatings.

 

[dcg9381]

Disagree. Sorry but it is incorrect to say that polyuea magically adheres to concrete without surface preparation. If anything you need even better prep with polyurea because of how fast it cures compared to epoxy.

Note, I didn't say no surface prep. I said that grinding was not necessary for installation (in my experience) - like many others, I've had success with acid etch. (New concrete)

In the end, I'm no expert on installing. I defer to LegacyIndustrial. What I can say is that I've done 1500 sqft of residential (water based stain, 2 coats of polyurea) and 3000 sqft of industrial with absolutely no adhesion issues for 4 years.

I've done catalytic epoxy before and it's turned out great, but in terms dollar per sqft AND work required to get it installed properly, you're going to have to drag me kicking and screaming to another product.