Your best bet is to remove the grout and replace with new grout as it has worn out. Go to a tile store or a big box store where they have people to help you out in replacing the grout.
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We have a tiled shower stall (the walls are floor tile and the front is glass block). Over time, the grout has cracked and the shower leaks. We have tried sealing with clear silicone putty but mold keeps growing underneath it and I have to peel it off to clean. Does anyone have a better suggestion? I would appreciate any help as this is very frustrating. Thank you.
Kerry from Poteet, TX
RE: Repairing Grout in a Tiled Shower
Have you tried the putty that has the mold repellent? I would clean it thoroughly using Clorox and water and let it dry real well, then reapply sealant. For some reason moisture is getting under your silicone to cause the mold. (07/01/2007)