Bathroom Vent Through Wall Or Roof

This old house general contractor tom silva shows how to properly install a roof mounted bath fan vent.

Bathroom vent through wall or roof.

A vent is an important part of a drain and it performs two functions. The 2018 irc contains the same language. I prefer to run a bath vent to outdoors via a horizontal line that goes across an attic and out through a gable end wall or one that vents down and outside through a roof overhang or soffit. See below for a shopping list and tools subscribe.

Depending on the location of the bathroom it may be easy to vent the exhaust fan through the roof. Some veteran builders used to consider a soffit as an appropriate placement for the event outlet but section m1501 1 of the 2012 international residential code irc changed the language to disallow exhausting through a soffit vent or ridge vent or into an attic or crawl space leaving a side wall or roof as the only two options. 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. If you vent through the roof condensation will drip back into the interior.

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. 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. This involves running ductwork from the fan usually though an attic and out through the roof. Bathroom ventilation fan duct routing routing a bath vent duct down out or up through an attic or roof out.

Venting through a roof vent or exhausting them in the attic could cause moisture problems and rot. The best exhaust fan venting is through smooth rigid ducts with taped joints and screwed to a special vent hood. In all cases the ducting needs to conduct the exchaust to the building exterior and needs to terminate in an animal proof vent cover. It eliminates the need for routing ductwork through the house and these fans usually dry the bathroom more quickly.

Bath exhaust fans routed up through the roof. This discussion is now found at bathroom vent up through roof. Going through the roof guarantees it will go up in the air and away from your home i would love to see a copy of the building code that suggests venting a bathroom fan through the soffit is recommended. Vent your bath and kitchen exhaust fans through the roof through a special roof hood.

The alternative to a roof exhaust if you re concerned about not being able to seal the hole in the roof is to exhaust through a gable end. The first is to allow air into the drain line to replace the vacuum created by flowing. The 2nd bathroom vent drips on the floor and is ruining the ceiling.