What Type of Contractor Redirects a Bathroom Vent from the Attic to the Outdoors?

3 pros!
Question by Guest_97483255: I just learned that both of my upstairs bathrooms have fans that vent the air directly into the attic. I would like to have this corrected so they vent to the outdoors. The fans themselves are new, so don't need replacing (which I assume would be the purview of an electrician). I'm not certain who to contact for this job - an HVAC person, a roofer, a handyman?
Answered by BayAreaAC: Per the buiding code, here in Florida, roofer to go thru the roof and a HVAC contractor to run the duct. HVAC guy may sell and install the fan also. This varies around the country, but you were on the right track.
Source: www.bayareacool.com
Answered by hosey: Any person competent in installing an outside vent- either thru the roof, soffit, or gable/hip end of the house thru the siding. Each bath fan should be on a separate 4" or larger duct and the outside vent portion must have a baffle/damper to prevent anything from coming into the duct work.. While in the attic, I would have that person measure the amount of insulation, check for soffit ventilation and/or gable end vents, and sair seal any penetrations from the living area, ie electrical, plumbing, chimney chases to reduce air leakage.
Answered by LCD: I would use a roofer - I just don't trust HVAC contractors with roof penetrations - as evidenced by the shoddy work done initially in your case, with it just being vented into the attic, though that may have been a general contractor failure in not ensuring the penetration went through the roof when the roof was put on.
Make sure they do not just stick a piece of vent pipe down through a hole in the sheathing - the duct has to be sealed - seam sealer is best, duct tape poor mans alternative, and where the duct penetrates the sheathing it should be sealed to the sheathing with a roof jack so moist air and moisture accumulating in the vent hood does not come back down into the attic or saturate the edges of the opening in the sheathing. This is double important if you have winters in your area, as the moist air condenses in the vent hood and accumulates, so you can get a nasty rot situation if it has access to the sheathing - should be fully ice and water shield protected under the hood, with the ice and water shield "daylighting" a shingle row downslope of the vent hood metal to drain out any accumulated water. Better solution - avoid the hood entirely (if legal in your area) and go with an insulated vertical or U-shaped exhaust vent with flapper and screen.
Answered by danieljimenez0: It's an incredibly easy fix, but person has to feel comfortable walking around attic without going through the ceiling. LOL
In CA, this is a under $500 plus parts, one day fix for both ducts -so any handyman can do this work.
I suggest though, that you go through the gable because whenever a properly installed roof is touched, it invites water. A gable has no direct water intrusion and usually is easier to put in and repair.
Good luck.
Dan
Harvard Construction
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