Dear Merci:
“
We were told to seal it every six months and afraid we have not.
”
Thank goodness you didn't!
“
He told us that mastic will mold and they should have used thinset.
”
I really don't know if this is true. But if the mastic is not activated by water, it should not mold by itself. Which bring us to the only possible problem I can think of:
You must have water behind and under your travertine tiles.
Now, how did the water get there?
I don't know: only a physical inspection of your stall could determine that; but if I have to guess, I would have to assume that either you have no grout (maybe the tiles were set butt-joint) or some of the grout is missing or damaged.
And, BTW, you don't say anything about this, but your travertine is filled, right?
What to do if I'm right on the money?
Considering that travertine is one of the best stones for shower enclosures (providing that's filled, of course) due to its natural high-resistance to mold and mildew, when it begins to display mold and mildew throughout its texture, I'm sorry to report that usually the situation is too far gone for any possible repair.
I hope I'm dead wrong on this one, but it may be jackhammer time, alas…
L
If the tiles were set butt-joint, than there's no doubt. What could one possibly do about it?
Let me know what your inspection will bring into the open and see if there's any hope.
And, in the meantime…
May I ask you to please read and e-sign our Statement of Purpose at:
http://www.marblecleaning.org/purpose.htm?
Ciao and good luck,
Mauri
Article ID: 1251
Created On: Sat, Feb 23, 2008 at 11:34 AM
Last Updated On: Sat, Feb 23, 2008 at 12:00 AM
Authored by: Maurizio Bertoli [mail@mbstone.com]
Online URL: https://marblecleaning.org/knowledgebase/article.php?id=1251