New sealed shower grout darkens when wet

[Steadygirl]

We just had some contractors re-grout the tile in our shower and bathroom floor but something seems to have gone wrong.

After putting in the new grout (non-sanded), they applied sealer about 36 hrs later. 48 hours after the sealer was put on we used the shower and noticed that where the water hit the grout it was turning dark, like it was wet.

We read the bottle of sealer they used and noticed it said "not for use in wet areas". So we assumed the grout hadn't be properly sealed and had them come back and re-seal it with a sealer for bathrooms.

But 48 hrs after the second time they sealed it with a bathroom sealer, we used the shower and the grout is still turning dark in places. It turns light again a few hours later, like it has dried out, but while it's dark it looks very unattractive and I've never seen grout do this.

The contractor says he doesn't know what is going on but has offered to take out the grout and start over. But what can he do differently this time, other than use the correct sealer in the first place? Has anyone seen this problem before?

[cx]

Welcome, SM.

Please name names here.

1. What sealer was used the first time?

2. What sealer was used the second time?

3. What grout was used?

4. Did the instructions on the first sealer actually say it could be applied only 36 hours after grouting?

5. Did the instructions for the second sealer indicate it could be used effectively over the first sealer?

[Steadygirl]

The grout was polyblend non-sanded grout from Home Depot.

The first sealer was TileLab gloss sealer and finish. It said grout should cure for 48 hrs before applying the sealer, and said the sealer should be used in dry interior areas only. So obviously the contractor applied the sealer too soon, and used a sealer not appropriate for a bathroom.

The second sealer was TileLab grout and tile sealer. It says it should be applied to a clean surface free of finishes, and after grout has cured for 48 hrs.

So, is the darkening of the grout a result of the sealer being applied before the grout had cured for 48hrs? And adding more sealer didn't help?

[Davestone]

The first sealer is a topical sealer that shouldn't be used in a wet area,or over grout joints for that matter.This sealer will peel off with moisture and also didn't allow the second sealer to penetrate and work.
The first sealer needs to be stripped,then the second sealer applied.

[Steadygirl]

Thanks. We had them take out the grout and re-grout, and wait 4 days and they're coming back Monday to re-seal with Tile Guard penetrating grout sealer. Hopefully that will result in grout that doesn't change color when it's wet.

[Davestone]

Tile Guard isn't exactly a great sealer so use a couple coats if u use it.

[Steadygirl]

OK, thanks. I'll see if I can find a better one - what would you recommend?

[Davestone]

Honestly i don't know what they have in your area.

[Steadygirl]

The Tile Store gave me some Penetrating Sealer made by Superior Adhesives and Chemicals.

[StoneTooling]

Sealers by Miracle Sealants, Aqua Mix and Dupont's StoneTech Professional pretty widely available in most local markets and online. I would stick with, what I consider, the best.

[doitright]

Hi SM, Welcome!

We could use a first name vs. initials.

The Superior Impregnating sealer from "The Tile Shop" will suffice. Make sure the grout has 72 hours to cure prior to applying. More that likely it will need a couple of saturating coats. Be sure to not let the sealer dry on the face of the tile.

[Steadygirl]

Well, my first name is kinda long so initials work best.

As many of you suggested, it will need more than one coat. The new sealer was put on yesterday morning and I just splashed some water on it - still turning dark. It only got one coat because we ran out of sealer (I only bought a pint, and the contractor did the tiles as well as the grout).

Tired of calling the contractor to say the job STILL isn't done right, we are going to finish the job ourselves. So, after I let the area I splashed dry out again, should I use another coat of the same sealer (Penetrating Sealer made by Superior Adhesives and Chemicals) or order some really high-quality stuff like Stone Tech, Aquamix, or Miracle 511? Can I put a coat of something different on top of the first coat?

[Steadygirl]

Hmm, what is the deal with all the different products within the same company? This is what Amazon sells:

Miracle Sealants 511 QT SG 511 Impregnator Penetrating Sealer, Quart $50
Miracle Sealants PLUS PT SG 511 Porous Plus Penetrating Sealer, Pint $60
Miracle Sealants GRT SLR AERO SG 511 Spray On Grout Sealer, 15-Ounce $13

Aqua Mix Sealers Choice - Quart $37
Aqua Mix Sealers Choice Gold - Quart $42

Stonetech Grout Sealer - 1 Qt. $19
StoneTech BPSS12-32 BulletProof Stone Sealer, 1-Quart $44

Is the Miracle "Porous Plus" that much better than the "Impregnator"? Are the more expensive products made by Aqua Mix and Stone Tech worth the extra money?

[StoneTooling]

Those prices are pretty hefty for those products. I love Amazon but for our industry, they don't really have the best pricing.

[Kehraus]

Grout that is sealed can still 'darken' when exposed to water.

The real question is: how long does it take to go back to the dry color?

Most sealers on the market today are a penetrating type, and seal from below
the surface, this leave the top minute layer without anything on it.

If your grout goes back to color within an hour, it is sealed.

Grout that isn't sealed would be wet looking for hours after the water
exposure.