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My sister asked today about the formation of mildew in her bathroom in the corners near the ceiling. I know that it’s caused by her 20 minute HOT showers. Anybody have any ideas on how to remedy the situation? I’m thinking maybe a larger exhaust fan and how to kill the mildew?
John
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john .. try a smoke test.. but it sounds like a bigger fan is in order...
*Mildew is an organism.Use peroxide on it.
*Often, that's an indication of poor or missing insulation: the cold section of wall causes condensation; mildew uses the water to grow.
*Actually all 3 responses sound great. -I'm thinking bigger fan because of her wanton waste of hot water.-I didn't know about peroxide, I was thinking bleach. But I'll try it.-And we were getting ready to add more insulation. The old rock wool insulation has settled to about 6" deep. Adding cells on top would probably help a bunch.Thanks,John
*Repaint ceiling with mildew-resistant ceiling paint.Undercut bathroom door to provide makeup air to fan.Shorter showers.
*Peroxide is a bleach - just not chlorine. Use either one but I'd rather have peroxide running down my elbows or dripping in my face.You see this mostly in the corners because you have dead air flow their regardless of the size of the fan. That is why they recommend placing smoke detectors at least 18" away from the walls. You can also get more condensation there because framing places solid wood at that point for thermal bridging, creating cold spots. Best bet is to wash down with a bleach and paint with a mildewcide containing paint. Shouldn't need anything more extreme.No need to adjust her lifestyle. One of lifes few legal and moral pleasures is a good hot shower. Too bad you can't combine that with another of those pleasures - reading a good book.
*I'll let her decide whether to use bleach or peroxide. I've never known anyone to spend so much time in the bathroom. I'll try cleaning off mildew and adding insulation before changing fan. That fan's been in there for 26 years and never had a problem before. Just recently.Thanks,John
*If the problem has just started recently make sure that some critter has not built a nest or some thing blocking the outside vent.
*Mix clorox with water and spray it from a plastic spray bottle to bleach out mildew. Or check in the housekeeping dept. of the grocery store for a commercial product in a sprayer. In either case, little or no dripping.
*Zinzer makes an excellent mildew resistant paint that works well for me. I used semi-gloss white on the ceilings and had the white tinted to the color I wanted for the walls. It tints darker than regular paint so use 80% of the tint called for like the label says but I didn't do on the first coat. (I wanted peach and got pumpkin!) All of the other suggestions are good too. What ever paint you do you must kill all the existing mildew first. Bleach is the best. Comet works well because it contains bleach along with an abrasive which makes for effective scrubbing, and splashes less. Be sure to rinse well. Have fun.
*Bleach seems to be the winner for instant results, but better ventilation is the solution to the larger problem. We had horrible problems with mildew until we installed a vent fan during a remodel of the bathroom two years ago. It took care of 99.9% of the problem. Now I only occasionally see a tiny bit of mildew on the ceiling, so it ends up getting the treatment once or maybe twice a year. I just recently had my annual bleach blast. I learned something new as a result. If you plan on wielding the bleach spray bottle, even if you think you've gotten all the bleach off the ceiling after letting it sit for a few minutes, double check for overspray on the walls and trim. You might have missed some. A stream of bleach running down the wall will do it's thing on your paint while you're not looking. A little payback from the mildew apparently...
*Thanks guys,I'll pass all the info on to sis. For once I let her get her hands dirty on this one.John
*1 cup bleach in the bottom 1/2 of a cut off 1 gal plastic bottle on the counter. Slowly over 3 or 4 seconds add 1 cup vinegar (5% acidity.) Leave the room and close the door. Wait 24 hrs. The room will fill with dilute chlorine and chlorine oxide gas. After 24 hrs, open the door and turn on the exhaust fan. Leave the door open a crack and run the fan 3 or 4 hrs. No drips, no mildew. I do this every month in the wine cellar, 9'x18'x8'high, and it has eliminated serious mold that was tough enough to beat me arm wrestling.
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My sister asked today about the formation of mildew in her bathroom in the corners near the ceiling. I know that it's caused by her 20 minute HOT showers. Anybody have any ideas on how to remedy the situation? I'm thinking maybe a larger exhaust fan and how to kill the mildew?
John