Mold and Moisture Problems in Baths


Can you explain what I need to do to clean and restore or replace the grout in my tiled shower? The tile is 4″ x 4″ with white grout, and despite my cleaning it gets black and moldy every week.
MarvA 7-12-08

The place to start in this case is with the overall moisture situation in your bathroom. If the space were properly ventilated, that mildew wouldn’t be making a weekly appearance. One way to stop the show and related health threats is to install a vent fan on an occupancy sensor.  This combination can be set to let the fan run 10-15 minutes after you leave the bath, doing a better job of evacuating moisture from the space.  Combination fan/light units like those from Broan-NuTone can include features like these that provide powerful ventilation and lighting, along with a quiet fan. Finally, remember that vent fan units must exhaust to the outside of your home and not into your attic!

After your bathroom’s ventilation problem is solved, restore tiled shower surfaces by using a grout saw to scrape out the existing grout material, and replace it with an antimicrobial grout that’ll resist future settlements of stain-causing mildew and mold. Laticrete offers a great solution for this step with its antimicrobial 1500 Sanded Grout and 1776 Grout Admix, both of which contain the mold-and-mildew-inhibiting protection of Microban, and also eliminate the shading and blotching caused by minerals and organic particles commonly found in domestic water.

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