Question - Where do bathroom vents vent to?

Answered by: Jeremy Phillips  |  Category: General  |  Last Updated: 20-06-2022  |  Views: 968  |  Total Questions: 9

Bathroom vent fans must be vented to the out of doors. Venting this fan into the attic is simply asking for problems. The excessive moisture will cause condensation on the roof members, insulation and eventually cause mold. It is never OK to vent directly into an attic even if the attic itself is vented. Each bathroom has its own exhaust fan; each fan vents separately out the roof. But while you can't have two fans with one vent, you can make one fan and one vent serve two bathrooms. This setup requires an in-line centrifugal fan mounted in the attic drawing air simultaneously from both bathrooms (see photo). It is not uncommon for bathrooms of different apartments in a multi-unit building to be connected to the same exhaust plenum. The plenum, in turn, is usually exhausted through the roof with a fan that pulls the odors out. In this way you can exhaust the bathroom air as you need to. The primary purpose for having an exhaust fan is to remove the moisture out of the bathroom. These fans help to control and eliminate bathroom odors. Additionally, they add to the safety of the home and its residents by reducing fumes from cleaning agents that could potentially cause health-related issues. Smooth metal duct also maximizes vent fan airflow performance. But flex duct and insulated flex duct are approved by bath vent fan manufacturers are very widely used for fan venting because of its ease of installation and low cost, as we describe next.

https://www.homeadvisor.com/cost/bathrooms/install-a-bath-fan/

Cost to Install Bathroom Exhaust Fan Through Roof A bathroom exhaust fan costs between $15 and $300. With labor, expect to pay $60 on the low end and $500 on the high end. This cost depends on the fan price and the project difficulty. You can also redirect air and moisture outside with a roof vent.

https://www.uexpress.com/first-aid-for-the-ailing-house/2012/11/23/there-are-lots-of-wrong-ways

If the soffit is unvented, venting the bath fan through it is possible, but be aware that the moisture the fan exhausts can cause mold to form on the soffit board and stain it. Running any duct through an outside wall should not be done because it will get cold, which would cause condensation.

https://www.islandbathrooms.co.uk/how-to-ventilate-protect-your-bathroom-from-moisture-the-expert-wa

If you don't have a window (or a great extractor fan) then leave your bathroom door open when it's not being used. Also, take out any damp towels and hang them elsewhere so they don't add to the moisture already in the bathroom.

https://diy.stackexchange.com/questions/13477/does-a-bathroom-exhaust-fan-have-to-vent-to-the-outsid

Bathroom vent fans must be vented to the out of doors. Venting this fan into the attic is simply asking for problems. The excessive moisture will cause condensation on the roof members, insulation and eventually cause mold.

https://www.chicagotribune.com/real-estate/sc-housing-ask-builder-consumer-0331-20160331-story.html

The fan exhaust must vent directly to the exterior of the home. Do not put the vent termination in a roof overhang or soffit. Don't put it on a wall near or under a roof overhang. The moist air that's belched out by the fan can be sucked right up into the open soffit vents and be drawn into your attic.

https://www.askthebuilder.com/diy-bath-fan-vent/

I'd give serious consideration to using foam core PVC pipe as the vent pipe for your fan. The fittings can be glued and any water that might form in the pipe will never leak onto your ceiling or down a wall. The fan exhaust must vent directly to the exterior of the home.

https://www.familyhandyman.com/bathroom/exhaust-fan/better-insulation-will-prevent-water-stains-arou

If bath fan ducting isn't properly insulated, the moist air from your house will condense inside the duct. The first step is to head to the attic. You may find that the insulation simply needs to be refastened. If your ducts are properly insulated, another potential cause of condensation is lack of use.