Condensation on soffits after painting
bmershon
| Posted in GBA Pro Help on
I have a split-level house that has an second-floor overhang with soffits where the a/c ducts terminate to supply the 2nd floor with a/c and heat. We repainted the exterior of the house a week ago and now exterior condensation is forming on the soffits directly below the a/c vents. I’ve lived in the house for 10 years and we never had any issue like this that I’m aware of. This condensation keeps the paint from drying/curing. What should I do?
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Replies
It unfortunately makes sense that that would happen.
Short term, you may need to turn off the AC completely, or at least close off those particular A/C registers, until the paint cures. I'm not sure it will cure properly after sitting damp--you might need to wipe and/or sand it off and re-paint. Or you could wait until fall to do that, when you don't need the A/C
But that is a clear indication that you have ducts near the exterior with minimal insulation. So you may want to add insulation. Perhaps EPS foam board under the whole length, covered by plywood.
What climate are you in?
Buzz,
Here is a link to an article that discusses your situation: How to Insulate a Cold Floor.
The article includes the illustration which I have included below.
In that article, I wrote, "If HVAC ducts are routed through the floor assembly, the floor joists must be deep enough to install several inches of insulation under the ducts. A floor with ducts also should be insulated with a continuous layer of thick rigid foam under the floor joists."
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