Hi all. I had this walkway done a few years back (over 5 years easy), and the contractor said to coat it with TIAH, which was just fine until a few years ago when i bought a jukebox and decided to roll it up to the front door. Yep, you guessed it, nice tracks in the sealant coating. So I stripped it and redid it and (there is a 50 cent word for this I know) it keeps blushing out in a whitish haze. I have tried stripping it and resealing it twice (the last 2 years) and keeps doing this. I currently have it stripped again and there still seems to be some of the original coat of sealant on it. I don't know if this is the cause or not. I thin tried a bit of fine sandpaper and this seems to have no effect. Although I was chickening out because some colorant was coming off with the water I was using to sand with, and I was worried it wold ruin the look. Even now if it gets rained on it looks really nice, but want to know what I might be doing wrong to not get a good refinish job. I strip it with orange-based strippers and a pressure washer. Maybe I need to strip it differently, or use some other sealer? I am planning on waiting to reseal also when we get a dry spell so I know moisture in the concrete isn't the problem.
Gilly

 

It sounds like moisture in the concrete IS the problem. You may need to switch to a different, more breathable sealer, or wait longer after stripping to reseal.

 

TScarborough is right about the moisture. When sealer whitens, it means moisture is either trapped under the sealer, or that the sealer is delaminating. A quick fix is to spray a heavy coat of xylol (xylene) on it and let it evaporate. This reconstitutes the acrylic solids of the sealer. Usually, after the xylol evaporates, the whitening is gone. If spraying alone doesn't do it however, you may need to scrub the xylol in with a natural bristled acid brush. Make sure you use natural bristle because xylol wil melt a plastic bristled one.
After that, if you intend to reseal, make sure the slab is COMPLETELY dry. Not just looks dry, or feels dry, or seems dry. Let it dry for a MINIMUM of 24 hours before sealing. When you seal, make certain to put the material on as thin as possible, with no puddling. One coat should be sufficient. Putting too high a build of sealer on is worse than not putting enough on. Good luck.

Pecos

 

Not rinsing off all the citrus stripper could leave residues that could be part of the problem. The problem with surface sealers on concrete is that if water vapor or moisture or excess moisture penetrates the pores in sealer while drying it will turn white. Even if it is a hot dry day when sealer is applied, humidity can be a problem. Heat can also be a problem, especially if temperature is near 90 or above. If topical sealers are used, it's best to do so early in the day right after the dew dries.

 

Pecos
There is a slight white film even after stripping when the concrete is dry. If it rains a little it looks fine. Is this a problem?
For applying, is brushing the best, or a roller, or tank spraying?
I'd like to get the last of the sealant off, would the Xylol and a rag work? It's really ON there. I think it's from the original coat. Everything was fine until I damaged it with that jukebox (heavy and has metal casters....OOPS!!!)
Gilly

 

Xylene on a rag will get some more of the old sealer off, but may not be completely necessary. If you just spray the xylene on and scrub it with the acid brush, it should clear up what's on there now. Then, just use a roller to put on another coat, or spray it on if you can. I prefer the roller though. We also add H&C Shark Grip (Sherwin-Williams paint stores) to our sealer to make it more slip resistant.
What Twelvepole said about the citrus stripper is right on. If you don't get it all off, it will keep your new sealer from setting up. It will remain tacky for a LONG time. Good luck!

Pecos

 

I do have a whitish residue after cleaning, sort of the same color as the colagulated (sp?) sealant that the stripper did remove. I dried water and a small wire brush and it didn't take off the stuff on the colored concrete, although the brush did work nice getting it out of the "grooves" between the colored sections. I'll try the Xylene on it. I don't think another session of citrus stripper will do much good.
Another thought I had is where I work they have one of these floor scrubbing machines they'd probably let me borrow for a night (heavy machine with a rotating disc with bristles on it for cleaning a mechanics shop floor).
Anyone advise one way or another on the TIAH sealer?
PS nothing seems tacky right now.
Gilly

 

I had the chance to buy some Xylol and tried a few areas and it did make those areas look like new. I used a small wire brush to scrub it and an old rag. I will try just coating it and letting it evaporate to see if the results are the same.

Any comments on the TIAH sealer? I have enough left to do it again but I sure would hate to have to strip this again any time soon!
Gilly

 

Tiah is a good sealer, you should use it.

 

I agree that TIAH should be fine. You just need to apply it correctly. That is: on a THOROUGHLY dry slab (24 hours minimum) and not too thickly. Roll it on as thin as possible and do not leave any puddles.

 

Thought I should to a wrap-up on this thread.

I did scrub it down with Xylol (was expensive to do as i used about 4 cans of it! Also used a wire brush scrubber we found at a big box store which attaches to a shop broom handle, screws on to the handle) and let it sit for a week, We had a rare dry week here in S Wisconsin so lucked out on weather.

Then did one last wipe down with Xylol (less than 1 can to do whole walk, we just used rags).

Wanted to spray it, but found sprayer i bought special (cheap) to do this 1 job would only squirt, no spray. Bummer.

Thinking fast, my wife grabbed a couple brushes and we both worked at squirting then brushing the TIAH on the concrete.

One thing we did different, besides trying to get the concrete as DRY as possible is to do it in the late evening to keep the sun from drying the sealer too fast, we wanted it to be gradual not in 10 minutes like it was taking in the sun.

It's been on for around 2 weeks and looking very good.

When it blushed before (twice), we could see it blushing in about an hour or two, so we think this problem is licked.

Gilly