What does the research say about duct cleaning and allergies?
The U.S. Environmental Protection Agency says that duct cleaning has never been shown to prevent health problems, and that studies have not conclusively shown that dirty ducts raise the dust levels in a home. The EPA does not recommend routine duct cleaning. It suggests cleaning when there is a visible reason, such as heavy dust or debris, mold growth, or pests.
That does not mean a cleaning does nothing. It means you should not expect it to be an allergy cure, and you should be wary of any company that promises one.
What usually matters more for allergies?
Dust and pollen reach your lungs from many places: bedding, carpets, upholstery, pets, open windows and the air that comes in with the weather. A few habits tend to do more than the ducts:
- Use the filter your furnace was designed for, and change it on the schedule in the manual.
- Vacuum often, ideally with a sealed-bag or HEPA-filter vacuum, and wash bedding in hot water.
- Keep indoor humidity in a moderate range. Many guides suggest roughly 30 to 50 percent, which also helps in a Wisconsin winter when heated air gets dry.
- Keep pets out of the bedroom if dander is the trigger.
If allergies or breathing problems are a real concern, talk with your doctor. We clean ducts; we are not a medical resource.
When does cleaning the ducts still make sense?
There are good reasons to clean even if the allergy payoff is uncertain. Visible dust or debris blowing out of the registers, a recent remodel, signs that mice or other pests got into the ductwork, or a long-neglected system in a home you just bought are all fair reasons. A camera inspection can show what is actually in there before you decide. See our guide to camera inspections.
If you suspect mold, cleaning alone is not the answer. The moisture that feeds it has to be found and fixed first, and a licensed professional can help sort that out.
Common questions
Will duct cleaning get rid of the dust in my house?
Not on its own. Most household dust comes from fabric, skin, pets and outdoor air, and it settles on surfaces and returns to the air. Cleaning the ducts removes what has built up inside them, but dust will keep coming from everything else in the house.
Does duct cleaning help with pet dander?
It may remove some pet hair and dander that has collected in the ducts and registers, but dander also lives in carpet, furniture and bedding. Regular vacuuming and a good filter usually make a bigger difference.
What should I do if I see mold in my ducts?
Do not run the system more than needed and do not try to scrub it yourself. Mold needs moisture, so the source has to be found and fixed. A licensed professional can inspect and advise, and testing can confirm what the growth is.
How do I pick the right furnace filter?
Use the size and type your furnace manual calls for. A thicker or finer filter is not always better, because very restrictive filters can choke airflow in a system that was not built for them. If you are unsure, ask a licensed HVAC contractor.
Want a hand? See our cleaning services or where we work.