Depending on the location of the bathroom it may be easy to vent the exhaust fan through the roof.
Bath fan vents to attic.
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.
In order to accomplish this the roof has to have a hole cut in it.
Bathroom ventilation codes require a bathroom exhaust fan to vent to the exterior not the attic for health and structural reasons.
Venting through a roof vent or exhausting them in the attic could cause moisture problems and rot.
Otherwise you re inviting a moisture mold rot insect problem in the building.
The correct way to vent a bathroom fan through an attic is to terminate the vent either to the roof or to the gable wall.
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.
A grille in each bathroom attaches to ducts which then fasten to a y connector at the fan.
Either way the vent will have to go directly to the outside and installed with a vent hood cover.
The exhaust vent must terminate outdoors.
It can be an ugly sight to crawl above a poorly ventilated bathroom s ceiling.
This involves running ductwork from the fan usually though an attic and out through the roof.
A single exhaust exits through the roof figure a.
This system is quiet too.
Look for the special fans starting at 160 at heating cooling equipment dealers.
You mount a switch in each bathroom.
When venting a bathroom exhaust fan make sure to vent the air to the outside rather than into your attic where it can cause mold and mildew to form.
Bathroom exhaust fans perform an important function by removing excess moisture from your home.
Do not simply terminate a bath vent fan duct in an attic as shown in our photo above nor can you just dump the exhaust vent into a crawl space nor into a closed wall floor or ceiling cavity.
If you vent through the roof condensation will drip back into the interior.
Vent your bath and kitchen exhaust fans through the roof through a special roof hood.
No you cannot vent your bathroom exhaust fan into the attic.
Bathroom fan vent code requirements include no venting to attic areas to help reduce mold or structural problems.
It is because of this that many builders tend to advise against this method.
Your attic is not a temperature controlled environment is never the same temperature as your living space and generally closer to the temperature outside.