Insulating and Air-Sealing Around Exhaust Vent Pipe in Conditioned Attic
New build, zone 2A. Conditioned/unvented attic…
Roof design is a standard gable-end roof that extends (on one of the “non-gable side”) over a covered porch. The porch will have a built-in grill with a vent hood above it. The vent hood won’t have a cabinet around it, i.e., it will be the kind that everything shows between the bottom of the hood and where it penetrates the ceiling. That means the outdoor vent hood’s exhaust pipe will run thru the conditioned attic to exit out the roof. There will probably be about six feet of vent pipe in the conditioned attic (between porch ceiling and roof above).
Should I do anything for the vent pipe in the attic? For example, should I put a plywood box around it in the attic, then seal and insulate the box so that the vent pipe is isolated from the conditioned attic? Or should I seal and insulate around the pipe in the attic where it enters and exits? Any other ideas?
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