getting rid of efflorescence???

[sheepnure]

I grouted my porcelain tile floor with Custom Building Products' Polyblend grout. After the grout dried, it was several shades lighter than it was supposed to be. If the grout gets damp or wet it darkens back to where it should be. The grout bag said that efflorescence can naturally occur... yadda, yadda, yadda. They said that if you did get it to call them.

I called their tech support, and they believed it was efflorescence. He suggested a 50/50 mix of vinegar/water, grout haze remover, or even a stronger acid. Then he suggested their "Grout Renew" product that would seem to be much easier. He offered to send me a couple bottles, and I tried it out. I initially did a 3" section of grout underneath where the range will go, and it looked OK. After a few days, that little section still looks good.

I went to do the rest of the floor, and the Grout Renew was an absolute PAIN to work with. I did a very small section of the floor. The product is to be brushed into the joints with a toothbrush, and the excess is wiped off of the tile. It is very difficult to wipe off the tile (with a dry rag), and the color actually seems to be lighter than what it's supposed to be. I stopped using the Grout Renew and mixed up some vinegar water.

The vinegar/water mix initially looked like it was working, but then the joints dried just like the other ones and now you can't tell where I even used the vinegar.

I purposely chose a very dark brown grout (Tobacco Brown) so that the joints won't ever look dirty, and it matched shades within the tile. Now the joints are much lighter than I'd like to have them and I want to fix it. What is going to be the easiest/most effective way to get rid of this?

Thanks!

[CanyonTile]

Question for you, did you ever seal this floor?

[sheepnure]

No. I didn't seal the floor. I had efflorescence before and sealed it, only to find that when the sealer dried, the grout color returned back to normal. This time I didn't seal it because I imagined that sealing the grout would make it exponentially more difficult to correct the color.

Any advice???

[Davestone]

Josh,the grout renew is to color over the exisiting grout.Not what you want exactly,unless all other cleaning fails.It can be a pain unless you follow the directions explicitly.
If i was you i'd use sulfamic acid crystals and a grout brush on a small area.You want this cleaner to bubble slightly when applied to the grout.It eats off a thin amount of the top grout to get to the real color underneath.After you need to rinse well with a little ammonia in the rinse water.

[CanyonTile]

Josh,
Try testing a small control area with a Oil Based Enhancing Sealer and seeing how it holds up. It may or may not do the trick, but be warned occasionaly Enhancer will cause the grout to become splotchy since it is absorbed at different rates through out the grout. It will be a coin toss, but you will not know if you do not try.

[Trask]

We went to Laticrete grout specifically because of this reason...Not a dark grout issue since...

I have dealt with this exact thing with Customs on Many Dark grout jobs. Best luck has been with Solvent based Stone Tech Enhancer..Let it dry completely and try a area out of the way first. Sometimes it returns..

I have tried every acid and acidic Efflorescence specific cleaner I could find with little or no good results.

[sheepnure]

Thanks for the advice. I know there's a lot of stuff out there, but I'd like to know what actually works. I've done two tiling projects before this one, and both times I used Custom's grout, and both times it dried several shades lighter. I was going to go with Mapei's grout this time, but their browns were nowhere near as dark as I wanted to go, and the laticrete was special order only and double the price of Custom. I guess I've learned several lessons here. I even used distilled water to mix the grout (but not for sponging the floor) hoping to eliminate chances of efflorescence. I'll let y'all know what works!

[Davestone]

I use all grouts and don't have many issues, but i also know it generally dries two shades lighter.I also think it usually is not effloresence as much as latex migration,due to too much water in rinse cycle, or not mixing long enough.
Try the acid and see what happens,sometimes this doesn't work but i believe it's because not enough acid or time was used.

[teeitup]

Loved your comment about too much water in the rinse procedure. We recolor at least 75 NEW grout jobs per year. I am convinced that the problem is latex migration. Often on the tans and light browns you see totally washed out color and then a few inches away you see a color that is much darker than the original color should be; classic latex migration, you pick up some pigment with the sponge and then deposit a huge concentration a few inches away. That is why grout manufacturers recommend gauze instead of a sponge. Of course almost no one does that. We don't do grouting but we sure fix a lot of discolored grout due to the migration factor. Keep the water level in the new grout low and consistent.

[Davestone]

That's a good point about picking up pigment and depositing it,i never thought of it that way.