Bathroom fan vent code requirements include no venting to attic areas to help reduce mold or structural problems.
Bathroom exaust into attic.
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.
So can you vent a bathroom exhaust fan into the attic.
It may also violate a shingle warranty.
Bathroom exhaust fans perform an important function by removing excess moisture from your home.
Your attic is not a temperature controlled environment is never the same temperature as your living space and generally closer to the temperature outside.
Bathroom ventilation codes require a bathroom exhaust fan to vent to the exterior not the attic for health and structural reasons.