Stamped Concrete - What is this?

[PressureWashE 14]

I asked this question over at ***, but i did not get much of a response. I have a large job Thursday morning, and the back patio is stamped concrete, The sections out side of her over hang have this white residue to it, i rubbed it with my hands but it did not come off.

I took a picture of what im talking, and what it should look like. Anyone know how to remove it.

John

[Celeste 341]

That is moisture trapped underneath the sealer. Lightly wipe the affected areas with a rag moistened with zylene/xylene - this will emulsify the sealer just enough to let the trapped moisture escape then the sealer will settle back out properly. USE the proper PPE - this is not a applicator friendly product! It's not difficult to perform, however, it can be time consuming, even tedious. Price appropriately!

[PressureWashE 14]

That is moisture trapped underneath the sealer. Lightly wipe the affected areas with a rag moistened with zylene/xylene - this will emulsify the sealer just enough to let the trapped moisture escape then the sealer will settle back out properly. USE the proper PPE - this is not a applicator friendly product! It's not difficult to perform, however, it can be time consuming, even tedious. Price appropriately!

Thank you, Where can i get that compound?

[Ron Musgraves 240]

Thank you, Where can i get that compound?

That looked like someone caulked that??????? Looks bad

Edited October 21, 2009 by Ron Musgraves

[Danny Bates 14]

Kinda looks like dried up chlorine from a pool.

[PressureWashE 14]

Kinda looks like dried up chlorine from a pool.

No pool in the backyard, I had asked her if she had a house washed recently but she said not for 5 years.

[Ron Musgraves 240]

Have you tried CLR on it yet, you may need pro chems for the removal. Dont use a tom of pressure until you find something that will lift it a bit.

[PressureWashE 14]

Have you tried CLR on it yet, you may need pro chems for the removal. Dont use a tom of pressure until you find something that will lift it a bit.

Thats what i would like to use is chemical agitation, That way I dont harm the sealer.

[PressurePros 249]

Celeste humbly didn't give her qualifications. She went to school to install and has experience with it. I'd follow her advice, John.

[Ron Musgraves 240]

Thats what i would like to use is chemical agitation, That way I dont harm the sealer.

I hate to say it I'm not sure you have any sealer on there.

[Ron Musgraves 240]

That is moisture trapped underneath the sealer. Lightly wipe the affected areas with a rag moistened with zylene/xylene - this will emulsify the sealer just enough to let the trapped moisture escape then the sealer will settle back out properly. USE the proper PPE - this is not a applicator friendly product! It's not difficult to perform, however, it can be time consuming, even tedious. Price appropriately!

I would try Celeste Idea, I still dont think theres sealer on the stamped concrete from those photos.

I think the white calcium or fertilizer from irrigation over flow or simply tap water from a garden hose.

[PressureWashE 14]

Celeste humbly didn't give her qualifications. She went to school to install and has experience with it. I'd follow her advice, John.

I think I will try what she recommend, But where can I find the compound she specified?

John

[PressureWashE 14]

I found it, I will post results tomorrow. I also purchased some chemical gloves.

So what is the application method, Dab on rag and slowly work it into the surface and move on?

[Adrian 155]

Respirator John,

Xylene is some potent spirits.

Gloves good. Respirator even for a short time of exposure.

[James 625]

Before u do anything. Do a water test see if that area absorbs water and if a sealer is present. If it doesn't absorb water proceed to what Celextra said.

[Scott Paul 164]

It is most likely one of two things:

Moisture trapped under the sealer. This causes sealers to turn "white". You do not need to wipe on the Xylene. You can pump spray it on.

A "cheap" sealer that has turned white from the sun. This usually only happens in the sunny areas. Meaning it still looks good where it is shaded.

My advice is to apply the xylene like Celeste said. Most likely it will look good when done. Problem is if it is a bad sealer then the white will come back in a few weeks or months. If that happens then you will need to strip it off. This stripper will work:

Paver and Concrete Sealer Stripper | The Sealer Store

[Scott Paul 164]

Oops double post

Edited October 21, 2009 by Scott Paul

[John Doherty 126]

That is moisture trapped underneath the sealer. Lightly wipe the affected areas with a rag moistened with zylene/xylene - this will emulsify the sealer just enough to let the trapped moisture escape then the sealer will settle back out properly. USE the proper PPE - this is not a applicator friendly product! It's not difficult to perform, however, it can be time consuming, even tedious. Price appropriately!

+1 and what Scott said.

[PressureWashE 14]

Oops double post

So if i pump spray it on, I just let it dwell untill it dries?

Also If i do the Sealer test to see if water is absorbed or not, Say a sealer is not present, What is a good way of removing this white.

Thank you all for this valuable help

Also There is some mold in the grout of the concrete, Should I pressure wash it to clean it, then when it dries apply the xylene.

Thanks

Edited October 21, 2009 by PressureWashE

[SeaScapes 14]

Yes just spray it on and allow time to dry. We use pump up sprayers for this all the time. You must be sure to keep everyone off it while the chems react. Last year we did a driveway and the home owner let his dog out and the dog ran across the driveway. Didn't hurt the drive to bad but it did sealer all over the dogs paws. If a person were to walk across it then the shoe prints would be in the sealer and would want to lift it off at the same time.

[Oxfordlawn 14]

Soooooooooooo.....how did this story end??? What worked and what was it??

[TNRoofCleaner 16]

John is not going to answer now his newborn is in the hospital.

[Tmrrptr 164]

Looks like eflourescense under the sealer, to me...

Probably what happened is the concrete was acid stained at the time it was stamped, then they did not wait long enough before cleaning and sealing it.

They probably did NOT clean it before sealing !

The Celeste method using xylene could work well to strip the sealer.

It's available at any real paint store.

...Gonna need a quality carbon mask for breathing...

And I'm not sure of the flash point, but that will be a factor, also.

Make sure the fumes don't get to the water heater, if it's outside, or the cooking range, if a kitchen window will be open near that patio.

It's real easy to accomplish spectacular things with painter's solvents that make a science project gone wrong look like a good day ! Exercise caution !!

Don't try to remove the eflourescence from the slab until it's dried for a day or so.

I'd begin with mild chems to avoid affecting the acid stain in the finish.

High pressure will easily destroy the cream coat of the slab... especially since it's been worked up a bit for use of the stamps.

Advise the owner in advance that distinct coloring that was once present will not return, even after you apply sealer once the eflourescence is gone, but it will be much nicer without all that white stuff.

Good luck with the multi-step process.

All good things take time, so bid it properly.

The client should be very pleased with the end product.

Best

.