Howdy!
I had a real shocking surprise when I went to my tub surround tile job today. The grout that we applied the day before had dried two different colors – one was the desired light brown (Polyblend “Haystack”), and the other was white! The discoloring occured randomly, sometimes a small spot about the size of a pea, sometimes for a few lineal feet, and sometimes over a few square feet. We cleaned between the tiles thoroughly before grouting, mixed the grout well, and the bag from the store seemed untampered with. I do tile installations quite a bit and have never seen this kind of ghosting before. Any ideas what may have happened?
Ian
Replies
Other than your explanation that you cleaned out good, it sounds like a textbook case of your thinset showing through. Odd, that. Jon, guy that works with / for me from time to time asked the same thing just a few days ago. I said buddy, grab a grout saw. He said "but it's inch mosaic!" And he had the sealer on. Oops. Well, sometimes you just eat a new floor. You can try grout stains. I haven't, but between friends indications and a neighbor who is "the best durn tilesetter you'll ever meet!" (his words) they seem hit and miss for success. Better luck on them if you don't put the sealer on. Worth a shot before you break out the spud bar. If you do try to cut the grout, that little Fein Multimaster is the cat's meow. It'd pay for itself on that job.
Should there absolutely no thinset in the spaces? I have never worried about removing the trowl lines before and have had great success. There is a band of slate mosaic tiles in the installation, and the interesting thing is that the grout in that part is fine.
Perhaps this is the job where I learn the joys of to removing grout....
Was the thinset completly dry before grouting, if not the moisture from the grout could pull some of the thinset upward and discolor it, it happened once to me on a job I was in to much of a hurry to finish. Or maybe you just got a bad bag of grout?
Good Luck
Here's a similar thread, there may be info there for you as well:
http://forums.taunton.com/tp-breaktime/messages?msg=24470.1
I've had a similar experience with some Custom Polyblend sanded Haystack that I got at an HD outside of Austin, Texas on the 11th of November and used on a floor. The color is pretty consistent with only a few dark spots but ten days after it's been grouted it takes twenty or thirty minutes of water standing on the grout joints before the water fully penetrates the grout and turns it a darker color. I've been setting tile for twenty years and I've never seen anything like this happen. Water usully darkens the grout immediately.
I'm wondering if we did get some bad grout. Where did you get yours, and was it sanded?
And by the way, does anyone have any advice on how to determine if it is just bad grout and what can be done about it?
Years ago I did get a bad batch from Custom. It was obvious it was bad, and the grout had to be removed and redone.
Called custom, played phone tag, eventually they 'fessed that they had problems with that lot, they're final offer was $800 and new grout.
The job was a cast iron tub/shower surround, the typical open wall was a framed wall with an arched opening for tub/shower access. Tiled with 4x4's on all four sides w a couple of ribons. Took about 7 hours to turn the grout into a nasty dust cloud. Not fun. But more fun than it would have been without the $800.
This is of great interest to me as I'm doing the sma job over the thanksgiving weekend.
There were several questions put to you I'm interested in your reply.
Was the thinset completely dry before Grouting? Was any thinset peeking thru the grout?
My addition is was it the "white" thinset or the regular uncolored that you used for setting the tile in place.
Is there any question on the mixing of the grout?
Sorry to pester you but your project is identical to the one I'm doing right down to the color.
Best of luck!