Can you wall mount a bath vent and point the exit downward?
Trying to exhaust a second story cathedral ceiling bathroom and the 2 options are:
1. Wall mount at the highest point and straight up and out the roof. This creates a roof penetration and is in the front of the house which is visually unappealing.
2. Wall mount at the highest point, point the exit down, go down 10 feet to the floor joists, horizontal and sloped 12 feet inside a floor joist, and exit through the rim joist.
I understand the backdraft damper will not work in the second case, and that could be fixed by using an inline backdraft damper, but I can’t find a manufacturer that allows their units to be mounted in this configuration. Is this only due the the backdraft damper, or will it cause damage to the fan to be in this orientation?
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Replies
DamionL,
If you can't find one that allows vertical mounting you can use an inline fan instead.
Fantech has quite a few models.
Malcom Taylor, I've considered that but installing an inline fan in between floor joists and sealing it up with insulation and drywall seemed like a bad idea for future serviceability, plus the in line fans are generally pretty large, so it will be more complicated to install that vs a wall mount fan.
Obviously no vendor is going to approve an install that's not in their service manual, but ultimately what I'd like to know is if a wall mount fan is only approved with the exit pointing up due to the built in damper (which barely works to be fair) or if there is some other technical reason that I may be missing. My gut tells me it's only due to the backdraft damper.
DamionL,
I can't think of anything that would affect the performance. They work on sloped ceilings.
I feel like I remember seeing that one or some of the Panasonic Whisper Quiet models could be mounted on a wall, so maybe search on their website.
The downside is the creation of a roof penetration, which can be prone to leaks if not properly sealed and maintained. Additionally, venting through the front of the house may detract from its visual appeal. Check bath planet reviews https://www.bath-planet.reviews/ . These guys will be definitely able to help.