So I just noticed mold spores on the ceiling next to the vent. Is there an easy fix/solution to mitigate this without having to to sand/prime/paint, etc?

TIA!!!!

Mold is nothing to screw around with. Do you know the cause of why you are seeing it on the ceiling?

If not in the bathroom I'd be a little concerned trying to find the cause

Spray it with Concrobium as a start. It will kill the existing mold spores.

Thank you all. I will do those things. It is in the living room. Bathroom vent looks good.

RoyVal said:

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I've been fighting this for a few years. Make sure you seal the little gap between the metal box and the sheetrock where warm attic air could leak through and meet the cold metal box inside the vent.

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I've got the same issue in my master bedroom. I fight it every summer. Definitely a small gap between the ac duct and Sheetrock. Anything in particular you recommend sealing it with? I guess I should climb into the attic and try to get more insulation around it as well.

SharkinAg said:

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RoyVal said:

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I've been fighting this for a few years. Make sure you seal the little gap between the metal box and the sheetrock where warm attic air could leak through and meet the cold metal box inside the vent.

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I've got the same issue in my master bedroom. I fight it every summer. Definitely a small gap between the ac duct and Sheetrock. Anything in particular you recommend sealing it with? I guess I should climb into the attic and try to get more insulation around it as well.

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I've used caulk, silicone, DAP, and then some...I think plain silicone seems to have worked the best.

I removed all the registers (plastic) in my house (1-2 at a time), cleaned them with a bleach solution, then let them soak in peroxide (to whiten them).

While the registers soaked in the peroxide, I re-caulked/foamed in the boxes to make sure there were no gaps, then sprayed a bleach solution on the box surfaces. After that dried, I sprayed a few coats of Kilz on the box surfaces to sort-of "seal" everything.

I had no idea about Concorbium until this thread. Also, I had an HVAC contractor seal everything from the attic side (for the 2nd story) while the attic insulation was replaced.

Haven't seen any return of mold spots, but I haven't looked in about a year.

We had a problem where the upstairs air conditioner drain was plugged and it was creating a damp area on the Sheetrock below as it was dripping and overflowed the drip pan. So make sure the air conditioning drain is clear as well and check it every year.

Water can travel as well especially along rafters as we had a roof leak as well and it took me a while to figure out where the water came from but we cured that spot in child's bathroom with kilz and painted over it and chalked where it was coming through. The roofers didn't seal a vent pipe and it came through every rain storm.