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Bringing conduit into thermal envelope – GreenBuildingAdvisor
- February 19, 2026
- Posted by: bmtko
- Category: Uncategorized
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This is a piggyback off a previous post. I have two conduits running horizontally across an exterior framed wall. Warm moist indoor air is entering it, condensing where the conduit touches the exterior OSB, and then dripping down the end.
I already plan on using duct seal compound on the ends to prevent air from getting in. I was also thinking about trying to bring the entire conduit run inside the thermal envelope.
Would it make sense to cut pieces of polyiso foam board and place them behind where the conduit runs against the OSB? Quite a bit of drywall would have to be cutout. The rest of the wall cavity would be insulated with fiberglass batts. The wall has 2×6 studs.
Climate zone 5A