Ask an Expert: Much ado about mildew

Q: My bathroom is totally gross because we keep getting mold on the ceiling.  Our landlord finally fixed it but how do we prevent it from coming back?

A:  Mildew is totally gross, and eradicating it can be a major pain. Prevention and early detection is key. I’ll assume that your landlord “fixed it” by removing the moisture ridden section of your ceiling and allowing the inside of the wall some time (at least 24 hours) to dry before patching it back up. 

Mildew thrives in moist environments, like bathrooms, so keeping water at bay is your first priority. If there is water slowly collecting in your walls somewhere, ideally, you should put a stop to it. This is not always possible if you live in a multi unit dwelling. If that’s the case I highly recommend priming your walls with some Latex Water Proofing paint like AquaBloc by General Coatings Technologies. This product, or others like it, will create a barrier between the inside of your bathroom wall and any grossness that may lie beyond. Waterproof primer costs more than the ordinary kind, but its well worth the extra cash. Even if you don’t think you need to, go ahead and splurge.

Now that you’ve treated your walls with waterproof primer, it’s time to apply your topcoat. Most paint companies manufacture semi-gloss and high-gloss mildew resistant paint*. My favorite is by Zinsser (they also produce a waterproof variety). The thing about pre-mixed paint that contains mildewcide is that they almost always are only available in plain (boring) white.

If you’d rather paint your mildew prone room any color other than white, you’re in luck.  Most (good) paint and hardware stores carry mildewcide additives that can be added to just about any paint.

You can bring it home and mix it in with your paint yourself or, if you are buying it with new paint, just ask the nice person behind the counter to add it for you and shake it up in the paint machine.

Due to the fact that normal use of a bathroom creates moisture of its own, eliminating mildew growth completely is not realistic. If your mildew issue recurs soon after you’ve attacked the area with the miracle products previously mentioned, you may want to consider installing a vent fan to help clear the room. 

Good luck!

* Note: mildewcide will prevent growth of mold and mildew on the paint film only, a good excuse to splurge on that AquaBloc.

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