Condensation concerns with pipe penetrations
I have a few places where I have pipes that penetrate my thermal envelope and I want to determine if I have any possible condensation issues.
1) My plumbing vent pipes (ABS) penetrate my insulated gable roof that stacks up as follows: 5/8 sheetrock (detailed to act as an air barrier), Insulweb netting, 9.25″ DP cellulose, Zip sheathing, 4″ polyiso, air gap, cedar shingles. The pipe penetrations are spray foamed and taped on the exterior.
2) I have a metal hose bibb that penetrates an exterior wall that stacks up similar to the roof, except it is a 2×6 cavity and the exterior insulation is 3″ of Roxul. The Siga Majrex acts as the interior air barrier and vapor control layer (note: I will fix the taped penetration in the Majrex that my plumber destroyed and I still have to patch the holes where the cellulose was blown through).
3) I have a PVC condensation pipe that travels from a wall mount unit to a sink location on the interior (you can see it above the ladder). Same stack up as the hose bibb and the penetration is air sealed where it enters the interior space.
4) Supply and exhaust pipes for my ERV penetrate my wall. Same stack up as the hose bibb. They are air tight on both the exterior and interior and the pipe in the conditioned space will have foil faced insulation.
Does anyone see any possible condensation issues in the locations described above?
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