We alway offer 1st grout painting after cleaning. But never in a shower. I typically charge 2.75 per sqft for 3/8 joint on 12" tiles. More for wider and or color change from dark to light colors because you have to do 2 coats. But the key is having the right tools to paint. I make all my own paint applicators. 2nd is re-grout, but that too can get complicated. I use a high speed grinder with a non-chipping diamond blade 5". It's super fast but you have to have an extremely steady hand and vacuum attachments don't work because they block your vision. So you need a tech to follow with a vacuum. Then you got to mask EVERYTHING TO THE CEILING.  Also have techs cut all the edges. I charge 3.5-4 per sqft. If you can't do it fast it's not worth it.
We also use a single jet extractor at 1000psi. With the truck mount. Often we have to do grout line scraping to to remove what won't blast out. Also leave grout repair open. You never know how much loose grout will blow out during this Prosess.
I alway get the grout color during the estimate and bring out grout sample kits . We use water bottles fill & label them and carry every grout color on the chart or at least try to. But it seems it's always the one I don't have or is out of. We also carry every grout caulking color sanded & non-sanded. 
Hope that helps.

Tony DeLuna
925-625-9625
www.PatriotStoneRestoration.com

On Jun 3, 2016, at 9:51 AM, Stuart Young <santafefc@sbcglobal.net> wrote:


From time to time we’re asked to clean and restore these old tile installations.  My guess is that this tile is about 50 years old, maybe older.  The problem is always the grout lines. they have become black over the years and the tile is white.  Does anyone know of a process that will get the grout back to white, or at least a lighter color? Sometimes in showers we see the same problem with 4”x4” tiles.  What can be done?

Thanks

Stuart Young
Santa Fe Floor Care

Begin forwarded message:

From: Stuart Young <santafefc@sbcglobal.net>
Date: June 3, 2016 at 11:39:58 AM CDT
To: santafefc@sbcglobal.net



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