How To Vent A Bath Fan Through The Roof

The 2 pipes one a 4 master and the other a 3 2nd do not go through the ceiling but into a common box that goes through the roof.

How to vent a bath fan through the roof.

If you vent through a soffit where attic vents are often located the moisture will get sucked back up into the attic or roof venting. The best exhaust fan venting is through smooth rigid ducts with taped joints and screwed to a special vent hood. I would recommend installing a bath fan with a new vent that goes to the gable wall roof or even the soffit last choice. A down through soffit exhaust vent design by leaving warm air in the exhaust duct when the fan is off creates a heat trap that reduces heat loss out of the bathroom through the exhaust fan duct when the fan is off in comparison with up routed vents or even horizontal vents through a gable end wall.

Pass the opposite end of the duct through the hole in roof. It eliminates the need for routing ductwork through the house and these fans usually dry the bathroom more quickly. Take the end of the duct with the connector fitting and attach it to bath vent fan. Bathroom ventilation fan duct routing routing a bath vent duct down out or up through an attic or roof out.

You may just want to go with a completely new vent the whole way most modern bathroom fans require 4 or 6 vent hoses for much better performance and lower noise. This involves running ductwork from the fan usually though an attic and out through the roof. I recommend that my clients vent their bath fans out a gable wall if at all possible when not using an hrv or erv that is. Run a thick bead of tri polymer sealant along the underside of vent hood.

If you vent through the roof condensation will drip back into the interior. Depending on the location of the bathroom it may be easy to vent the exhaust fan through the roof. The master bathroom and the 2nd bathroom vent through the roof and through the same opening. Bend over the tabs then nail the tabs to the roof.

This article describes routing bath exhaust fan duct upwards through an attic or roof space or downwards through a floor or crawl space. Next use aviation snips to cut slits into the sheet metal sleeve. Venting through a roof vent or exhausting them in the attic could cause moisture problems and rot.