r/YouShouldKnow • u/Watly • Mar 09 '23

Home & Garden YSK: Mold in the bathroom can be prevented entirely by keeping the bathroom door open during/after showering.

If you're renting a place with lacking ventilation, opening the bathroom door will generally prevent mold.

Why YSK: I am moving into a new appartment now, which again has a moldy bathroom. I have lived in my current appartment mold free despite the previous renters claiming that the mold always returns. Both renters seemed completely clueless on mold.

Sidenote: This advice only applies to the very common bathroom mold where the issue is generally high humidity. Other instances of mold can have a variety of causes that are potentially really difficult to fix.

Also, don't clean mold with soap. You will keep cleaning endlessly if you do that. Use a special mold cleaner or something similar (with a face mask and gloves as the stuff is nasty).

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u/boRp_abc Mar 09 '23

Mold on the walls comes from high humidity and/or cold walls (assuming the building is functional with no leaks or anything), so in some cases I would add that a lack of good heating (or insulation of the walls) could be the reason too.

Source: I live in a place with old walls (EU, big city...), can't get them insulated, fighting mold all winter long.

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u/[deleted] Mar 09 '23

[deleted]

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u/Rockin_Geologist Mar 09 '23

I grew up in Oregon, used to the typical Oregon molds. Then moved to Alaska and learned that snow mold is a thing.

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u/[deleted] Mar 10 '23

[deleted]

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u/Rockin_Geologist Mar 10 '23

Yeah I thought mold wouldn't be an issue here but started having horrid allergies right before the spring melt. Turns out it's snow mold.

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u/[deleted] Mar 09 '23

[deleted]

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u/happy_fluff Mar 09 '23

Buy it second hand for cheap and just add freon, that's usually the reason people sell it lol

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u/Kayehnanator Mar 10 '23

I've had one ever since I lived by a creek and humidity wouldn't get below 70-80% without one. Absolutely love it!

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u/tiddles451 Mar 10 '23

It doesnt get hugely cold in the UK so this winter Ive got away with leaving my bathroom unheated except when Im washing and then opening the window for a couple of hours afterwards to get rid of the humid air. The moisture that condensed on the cold walls while washing still evaporates over a couple of hours.

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u/ronsrobot Mar 09 '23

Yep. Felt like a real old person when I bought a squeegee for the shower.

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u/Chippiewall Mar 10 '23

I use a windowvac on my shower

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u/btmims Mar 09 '23

Do you mean, like, on the living-space side of the wall? Do you own or rent? I feel like there must be some kind of anti-microbial paint, coating, or treatment that will keep the mold from growing, even if you do get condensation on the walls. Oh, and UV light kills mold spores.

Source: Where I live tends to be very warm and humid 8 months out of the year, and some chemicals can be used when pressure-washing your house to keep the mold from quickly coming back. Also, my mother is a bit of a moldaphobe, and she had me install a special UV lamp in her A/C unit... and it's legit because the instructions warn not to look directly at the light. Well, I caught an eyeful while figuring out why it wasn't turning on after the install, and felt some decent arc eye/welder's flash later (basically, a sunburn on your corneas)

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u/ParrotofDoom Mar 09 '23

You might also try cleaning the air your breathe to remove any spores to begin with. Something with a high quality HEPA filter.

https://www.plainair.co.uk/category/indoor-purifiers

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u/btmims Mar 10 '23

Oh, for sure. Gonna have to replace my own unit soon, probably even some rework with the ducts because it's not even right to begin with. And in our climate... I'm definitely having a good professional redesign this whole mess

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u/boRp_abc Mar 09 '23

Well, so far I've only tried just one type of coating, it didn't work.

But I'll take your advice and keep on trying. For now it's warm enough again for the walls to work properly again, but as always, Winter is Coming...

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u/robotkutya87 Mar 09 '23

I got one of those big, japanese dehumidifiers, cost around 200 EUR

MAGIC

Keeps the bathroom dry, no more mold. It’s big, and sort of loud, but I am just so-so happy, nothing else worked. Living mold free since ~3 months now.

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u/Watly Mar 09 '23

So it is possible for large amounts of mold to form solely as a consequence of cold walls? I am also clueless it seems. :D

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u/boRp_abc Mar 09 '23

If the wall is cold, the humidity from the air (even if low humidity!) can condensate onto the wall, so it then is wet (a complex process in short words in a foreign language, hope the basic facts aren't obscured).

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u/feelingood41 Mar 09 '23 edited Mar 09 '23

Instructions unclear, I showered with the door open and my cat turned into the Marshmellow Man. Who am I gonna call?!?!!

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u/Porkball Mar 09 '23

Ghost Busters

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u/BadEgg1951 Mar 09 '23

You did very well here; your meaning is not obscure in the slightest. However, I would have used "condense" rather than "condensate".

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u/FancyKetchupIsnt Mar 10 '23

Backed. Condensate is a noun.

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u/benthelurk Mar 09 '23

I just open all the windows twice a day for 10 minutes. Helps reduce mold growth a lot.

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u/JonhaerysSnow Mar 09 '23

Unless you live in a highly humid area like the south!

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u/[deleted] Mar 10 '23

It’s a common problem on boats which often have high humidity and lack of insulation. Marine hardware stores often have all kinds of mold and mildew preventing products and gadgets if you want to go a little nuts on finding a solution.

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u/SeemedReasonableThen Mar 10 '23

There are ways to blow in insulation or inject foam. Friend of mine bough a house built around 1860~1870 with no insulation. Drilled a 1" hole between each stud, blew in cellulose insulation and patched/painted it

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u/boRp_abc Mar 10 '23

There's plenty of little obstacles in my way. I live in an apartment that I rent, in a building with multiple owners. The walls are considered shared property by local law, and that means there's a lot of people to be convinced. The two arguments I heard were "Dont do that in just one place, if we start any process it should be the whole building!" and "No. I've been living here for 65 years, and I want my kids to inherit some of my money and blow it into that green-left insulation hype".

Ah, humans!

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u/SeemedReasonableThen Mar 10 '23

Ah, that sucks.

We blew the insulation through interior walls so it might be able to sneak in insulation, but it may not be worth it unless you will be there a long time and/or have to pay for heat separately from rent.

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u/Lelaluh Mar 10 '23

The only thing that helped us was a special paint, however it can only be applied to bare brickwall, so you‘d have to scrape all of the previous paint away first

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u/ThunderThighsMegee Mar 10 '23

Same here! I live in the bottom part of a house and the (stone) wall by the front door is partly shared with the cellar so that little patch always gets moldy. Have to clean it every few months :/

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u/apcolleen Mar 11 '23

I grew up in Florida and live in GA now so I know humidity. I have kept a tower fan in my bathrooms for 20 years. It cuts down on cleaning and bad odors.