efforesce

[edvdb]

Hi, just joined this board. I'm having some trouble with a large job, at a car dealership. We applied approx. 4500 sq ft porcelin tiles and grouted with warm grey grout from mapei. We have considerable white showing in the grout lines. We cleaned a portion of this job with grout buster and it looks great. However I do not what to clean this entire area with grout buster, because of muratic fumes and the trouble they can creat. (we have had 2 bad experience with acid). I have heard that the a 50% solution of boiled linseed and turpine wiped of the grout would even out the colour of the grout. has anyone tried this solution. thanks fast eddie

[doitright]

Hi Fast Eddie (I love it!) , Welcome!

Linseed oil & paint thinner is not the solution for grout efflorescence (or latex migration).

There are detergents available that aren't as harsh as muriatic acid. Have you tried vinegar & water?

[thomasherbert]

I just finished setting 250 sq ft of saltillo and had grout haze and some efflorescence to deal with. What finally worked for me was a solution of Sulfamic acid. Mix the crystals in water 8-10 oz per gallon. It took the grout haze right off and carried the efflorescence away as well. Followed by two water washes, then a penetrating solvent based sealer to keep the efflorescence away. The top coat with whatever sealer. This was for saltillo, but should work fine for your purposes. Sulfamic acid does not have harsh fumes or attack metal like muratic. Good luck.
\
Thomas

[doitright]

Hi Thomas

Thanks for your input. Efflorescence removal is a tough topic. There are many causes, and just as many solutions for removal. Not any one method will always work. I have an instance that I'm currently working on, that even a hammer and chisel is just the beginning stage of removal.

Thanks again! Hope you hang around!

Here's the specifics of our problem. Perhaps you can help.

Our company owns a building in Vancouver, BC which was renovated in 1986. The renovation included the cladding of the exterior with 12" x 12" smooth glazed tile. The tile is set on mortar, over expanded galvanized steel mesh, on steel framing with a cavity behind, though I would say it was not designed intentionally as a rain screen cavity wall. The grouting is approx 3/16" and there are a enameled aluminum channels at floor and column lines to provide additional detail.

While tile is an impervious material I believe it is possible that some small amounts of rainwater may enter the cavity through any cracks in the grout or next to the aluminum reveals.

We are finding that over time efflorescence has emanated from the grout lines, building up on the face of the tile near the edges and sometimes running down the face of the tile. While the white powdery efflorescence can be remove with detergent, a dirty grey almost mineral-like buildup remains.

We have tried various cleaners, including muriatic acid which at a certain strength began to remove the gloss of the tile glaze, none of which has been able to remove the grey-brown build-up.

Suggestions?

Thanks
Rob

[Steven Hauser]

Hi Rob,

I think you have two problems.

1) You need to first stop water from getting behind the tile. This will stop the efflorescence. You may also have to replace some tiles because thier setting bond may be compromised now.

2) I think that the strength of the muratic acid caused the discoloration and new weakness.

Minimum:
I suggest regrouting and using a urethane caulking at the expansion joints and around the perimeter..

Then I would debate with myself on whether to apply a siloxane based impregnating sealer.

Good luck,

Thanks Samuel.

We are working on the regrouting and caulking now, but would really like to address the building looking dirty. Do you have any solutions for how to remove the mineral-like deposits on the tile as I described above?

Regards
Rob

[Steven Hauser]

I would start by pressure washing the tile with a neutral ph cleaner.

From there I would get in touch with Prosoco and ask their opinion.

BTW call me Steven

[Chris the Rep]

Eddie,


How large are the tiles, and how long have they been installed? Also, how long between installing the tiles and grouting? Knowing may help determine if it is efflorescence or if it is latex migration.

Boiled linseed oil and turpentine will make the joints black, and a dirt magnet. Pass on that idea...

Chris

[John Bridge]

Hi all,

I'm only here to welcome Eddie, Thomas and Rob to the forums. Hope to see you on the other boards as well.

Rob, You can probably blame it on acid rain, caused by all those polluters down in the Seattle area.


By the way, there are advantages to registering with us. No bad things happen to you. We do not sell email addresses, etc. We're very nice people here.

[doitright]

Hi Rob

Maybe the surface moisture (including carbon in the pollution), etching on the glaze of the tiles is causing the problem you're describing. I also have worked with Prosoco on exterior projects such as this. I wouldn't even try the pressure wash, without consulting with them 1st. I've heard of instances that stains have actually been driven in vs. being blasted out.