Stop Ceiling Condensation
LESLIE: Matt in Michigan’s got a moldy situation. That’s a lot of Ms. Matt, what’s going on?
MATT: Hey, I live in a house we bought about four years ago and the house is about 38 years old. Well, the beginning of every winter we notice condensation on the ceilings near the exterior walls. Single-story house and there’s – you know, there’s ventilation but there’s no attic or anything; you know, no livable attic up there. And we’ve tried to control it just with a dehumidifier in the basement and that doesn’t seem to solve anything. So I’m just wondering what may be a cause of this condensation and then – which, you know, grows mold eventually.
TOM: Well, the cause of the condensation is because that area of the wall is colder than the rest of the wall. And the reason that could happen is because there could be voids in the insulation there. There’s a tool called an infrared scanner that essentially allows an energy auditor to see through your walls and look for those types of spaces and once they’re identified then they can be insulated with like a blown-in insulation product or something like that. If you want to try to do a better job of controlling the humidity, instead of putting dehumidifier in the basement we would recommend that you install a whole-home dehumidifier. This is a type of humidifier that’s actually built into your entire HVAC system and, hence, it controls humidity in all rooms of the house; not just the basement portion of the house.
Now, if you see mold start to form in these spots, you want to attack it very quickly. You want to spray the area down with a bleach and water solution and if you stay on top of it then I don’t you have any safety or health issues. But don’t let it get out of hand because then it can really kind of grow crazily and really impact you guys.
MATT: Right, yeah. So, the whole-house dehumidifiers. I wasn’t aware those were made. Where do you get those?
TOM: Aprilaire makes a great one. It’s Aprilaire.com and they have to be installed by your local HVAC contractor. It’s a permanently installed unit but when they’re functioning they take out 90 pints of water a day.
MATT: Hmm, wow. OK. And I’ve heard of, basically, baffles go in the rafters near the roof.
MATT: Would that kind of thing help out in this situation to bring cold air further up into the attic?
TOM: Well, the insulation baffle, what that does is it presses down the ceiling insulation at the roof overhang so that the soffit vents will work and ventilate the entire roof space. So that really is disconnected from what we’re talking about here in terms of a cold spot in the wall. That actually happens above that.
MATT: OK. OK. Alright, well thanks for your help.
TOM: You’re welcome, Matt. Thanks so much for calling us at 888-MONEY-PIT.