How to Vent a Bath Fan Through the Roof | This Old House
Bathroom fans are vented via installed ductwork, either straight up to the roof with a roof vent cap, or they are vented out below the roof overhang. Ensure ductwork deposits the moisture out of the house and not into the attic, as this will cause mold and moisture accumulation.
How To Install A Bath Exhaust Fan | DIY
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