How often should vents in a house be cleaned?
Short answer. It depends on the vent: dryer vents should be cleaned at least once a year, bath fan grilles and HVAC return grilles every few months, and roof and soffit vents checked yearly and after storms. Cleaning the whole duct system is not routine maintenance; it is usually needed only when there is visible mold, pests, or heavy debris.
A schedule by vent type
- Dryer vent: clean the lint screen every load and have the full duct and exterior cap cleaned at least annually, more often for large households or long runs. Lint buildup is a fire hazard.
- Bathroom exhaust fans: vacuum the grille and fan housing every few months, and confirm the duct actually reaches the outdoors, not the attic.
- Kitchen range hood: clean or replace grease filters every month or two, depending on how much you cook.
- HVAC registers and returns: vacuum the grilles every few months, and change the system filter on the schedule your HVAC contractor recommends.
- HVAC ductwork: no fixed interval. EPA guidance says duct cleaning has not been shown to prevent health problems and is worth considering when there is visible mold, vermin, or excessive dust and debris.
- Roof and soffit vents: check yearly and after major storms, and clear pollen, leaves, and nests from screens.
Vents that connect to the roof
Several of these systems end at the roof or eaves. In many Georgia homes, bath fans and dryers exhaust through roof caps, and their dampers and screens clog with lint or debris. A clogged roof cap can push moist air back into the duct, where it drips into the ceiling. Any exhaust that ends inside the attic instead of outdoors should be corrected, since it puts moisture right onto the roof decking.
Signs a vent needs attention now
- Clothes taking longer to dry.
- A bathroom mirror that stays fogged long after a shower.
- Musty smells or stains on ceilings near fans.
- Birds, wasps, or debris around exterior caps.
Add these to your yearly routine with the Georgia roof maintenance checklist, and see roof ventilation basics.