My shower got water under it last year and I thought I would try and fix it. By the time I was done, I ended ripping out the whole thing and starting over. Not trying to hijack your thread, just thought I'd share what I did to mine. I did use the roll on water proof material under the shower and on the walls. I agree with re-applying the sealer. I do mine every 4 months now. Its easy enough to do and I hoe it helps in the long run. Your tile job looks really good on your shower.
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