Mold and Mildew Prevention

September 10, 2008 3:31 PM

What is the better mold & mildew prophylaxis: a steam cleaner, a dehumidifier, or something else?

My wife and I live in a ~900 square foot apartment. A few weeks after moving in we noticed an unpleasant musty smell. We quickly narrowed it down to the living room window unit, which had obvious mold growing on it. We cleaned the parts we could get to with bleach and installed new filters on it and the other window unit. The smell was better for a few days.

The problem is, the smell has returned, and lately it's been getting worse, but we haven't seen any visible mold. The apartment has always been fairly humid, and we think that may be an issue. Given limited funds, would we be better off investing in a steam cleaner for the carpet, a dehumidifier, or something else?

posted by jedicus to Home & Garden (9 answers total)

Best answer: In my experience, clean whatever you can find with bleach (as you did) first, then use a dehumidifier to keep it so dry that mold has no chance to get a footing again. It'll take a week or so though, to really dry things out well.

A dehumidifier is also a permanent, reusable solution that'll make things better indefinitely, rather than a one-time fix like a carpet cleaning.
posted by rokusan at 3:47 PM on September 10, 2008

Best answer: A dehumidifier is a wonderful thing. Might it be possible to also hire (or borrow!) a steam cleaner just to do the carpets once, if you're concerned that they may be a bit icky? I think I'd have more peace of mind knowing that they'd been thoroughly cleaned, and then kept properly dry after that - although you could always clean perfectly well by hand if a steam cleaner's not available, just buy the dehumidifier first....
posted by Lebannen at 4:24 PM on September 10, 2008

Air conditioners are truly the best places in the universe for mold to grow. I don't know why, but I can tell every time I'm staying in a hotel or somewhere with a nasty air conditioner. I wake up gasping for air at 3am.

Maybe a professional cleaning of those? Or some crazy bleach or peroxide treatment. :/
posted by rokusan at 5:05 PM on September 10, 2008

Vinegar might be a better option for air conditioners than bleach since you have to breath what blows through it. Vinegar won't smell good either but if you spray vinegar on your AC filter, I would think mold would be less likely to grow there and it won't kill you, afaik.

I use vinegar on my mildewed towels from our air-tight bathroom.
posted by metajc at 5:12 PM on September 10, 2008

Best answer: Your best option is a new unit. Failing that a combination of bleach and vinegar is very effective against mold. To an already dilute bleach solution add about an equal amount of vinegar as there is bleach. (the order of addition is actually important) A dilution ratio of 1 to 25 bleach to water would be about right, but you can google this stuff for more tips. The vinegar changes the pH and vastly improves the efficacy of the bleach.

Steam cleaning the carpet does not seem like the best solution if the smell is coming from the window unit. Steam is very effective against mold though. If it is in the window unit, the trick is getting everything hot enough. The metal tends to cool the steam before it can kill the mold completely.
posted by caddis at 5:39 PM on September 10, 2008

I saw this on a tile forum and have been trying it around my house recently. For my use, I reduced the total volume but kept the ratios the same.

1/2 gal. white vinegar
1/2 gal. hydrogen peroxide
1 cup boric acid
keep closed tightly
mix well - use in a spray bottle on a dry surface

The forum I got it from was:

http://johnbridge.com/vbulletin/index.php

I am not associated with that forum at all. I found it while doing research on impending bathroom remodels.
posted by Chickenjack at 5:06 AM on September 11, 2008

Bleach is an alkali. Vinegar is an acid. Mixing an acid and an alkali will give you water and some kind of salt, possibly in a rather energetic reaction (not so likely with dilute bleach and as vinegar is a weak acid); it will not give you any kind of hyperamazing cleaning product. One or the other - or one, let it dry, then the other.
posted by Lebannen at 11:14 AM on September 11, 2008

Best answer: Vinegar increases killing power of bleach
posted by caddis at 11:23 AM on September 11, 2008

Response by poster: Thanks for the suggestions, everyone! We ended up going with both a steam cleaner and a dehumidifier, as well as another round of cleaning the air conditioner, this time with the vinegar/bleach combination.

A few days later, the smell is completely gone. It's incredible how much moisture the dehumidifier has pulled out of the apartment, at least four or five gallons so far.
posted by jedicus at 3:31 PM on September 15, 2008