We ve also seen homeowners have to replace all their roof decking because it became rotted from the excess moisture.
Exhaust into attic.
Intake vents located at the lowest part of the roof under the eaves allow cool.
Venting into the attic sends excess moisture to that space which can cause mold and other problems.
And many building codes require discharging exhaust to the building s exterior so it s just a good rule of thumb.
It may also violate a shingle warranty.
The best exhaust fan venting is through smooth rigid ducts with taped joints and screwed to a special vent hood.
Although this isn t always possible in attic crawl spaces you should always insulate the duct to prevent condensation problems.
Because what happens is when the insulation gets moist from all that moisture that s being dumped into the attic it completely cuts down on the r value of the insulation.
You should never exhaust the bathroom fan directly into the attic.
No you cannot vent your bathroom exhaust fan into the attic.
You can find 4 in.
So you do need to get that vented outside whether it s through the siding with one of those trap doors that sort of opens out every time you ve got it on or through.
Duct already wrapped in insulation at home centers.