Air Duct Cleaning
Duct cleaning helps in specific situations. We explain when it makes sense, what a thorough job covers and what it should not be expected to fix.
On this page
What duct cleaning can and cannot do
The U.S. Environmental Protection Agency's guidance on this topic is direct: duct cleaning has never been shown to prevent health problems. Studies have not shown that household dust levels rise because ducts are dirty, partly because much of the dust in ducts sticks to the surfaces and does not enter the living space.
That does not make cleaning useless. It means it should be done for a clear reason, not as a routine cure for allergies or dust. We would rather tell you that up front.
The EPA also notes that some research suggests dirty heating and cooling coils, fans and heat exchangers can make a system run less efficiently. That is a reason to keep the equipment maintained, which is mostly the work of your HVAC contractor.
When cleaning makes sense
Based on the EPA guidance, consider having ducts cleaned when:
- There is substantial visible mold inside hard-surface ducts or other parts of the system. The cause of the moisture has to be fixed too, or the mold will likely return.
- Rodents or insects have infested the ducts.
- Dust and debris are visibly released into rooms from the supply registers, in excessive amounts.
Other reasons people call include moving into a home after renovation work that left construction dust in the system.
If none of these apply, and your main concern is general dust in the house, cleaning the ducts may not make a noticeable difference. Better filtration, regular cleaning of the living space and controlling humidity often do more.
How we assess it
Every visit starts with an assessment. We look at accessible registers, returns and duct sections, and at the air handler area when it is safe and accessible. We look for visible mold growth, signs of pests and debris buildup, and note duct materials such as sheet metal, flex duct or duct board. You get our findings with photos before any cleaning is scheduled. If we do not see a reason to clean, we will say so.
Something that looks like mold may not be. The EPA notes that only lab analysis can confirm it. If that matters for your decision, have a sample tested.
A proper job covers the whole system
The EPA says that if ducts are cleaned, the work should include all components of the system. Cleaning only the ducts while leaving a dirty fan or coil can re-contaminate them. A full job addresses:
- Supply and return ducts and registers
- Grilles and diffusers
- The air handler housing and blower area, as accessible
- Coordination with your HVAC contractor on coils, drain pans and equipment they service
The EPA also says debris should be collected with vacuum equipment that exhausts outdoors or uses HEPA filtration, that only soft-bristle tools should be used on fiberglass duct board and lined ducts, and that access holes should be sealed afterward.
Chemical treatments
Some companies offer biocides or sealants inside ducts. The EPA cautions that their effectiveness in ducts is not well established and that sealants are not recommended for routine use. Products should only be used as their labels allow, and only after cleaning. We discuss any product with you before use, and you can decline it.
Limitations
- Cleaning does not fix moisture problems, leaky ducts or poor filtration.
- Flex duct and duct board are delicate. Badly damaged or heavily contaminated sections may need replacement rather than cleaning.
- Ducts inside closed walls and ceilings can only be reached from the openings.
- Furnace and air conditioner repairs belong to an HVAC contractor.
If mold is found, the source of the moisture has to be found and fixed, whether that is condensation on the ducts, a leak or high humidity. Otherwise the growth will likely return after cleaning.
Keeping ducts cleaner
Change filters on the schedule your equipment calls for, using the filter type the manufacturer allows. Keep dust out of the system during renovation by covering registers and shutting the system off. Fix sources of moisture near ducts and the air handler. These steps do more for indoor dust than an occasional cleaning.
Questions to ask any duct cleaning company
The EPA suggests asking a few questions before you hire anyone, including us:
- Will the whole system be cleaned, or only the ducts?
- Can you show me the contamination that justifies cleaning?
- What equipment will be used, and where does the debris go?
- How will flex duct or duct board be protected?
- Will any chemical be applied, and why?
- Do you follow the industry cleaning standard published by NADCA?
Be cautious of very low advertised prices and offers that bundle sanitizers or sealants by default.
Next step
If you have seen mold, pests or debris coming from your vents, request an assessment. A team member will contact you to confirm a time.
Questions homeowners ask
Will duct cleaning help my allergies?
The EPA says duct cleaning has never been shown to prevent health problems. If allergies are your concern, talk to your doctor and look at filtration and moisture control too.
How often should ducts be cleaned?
There is no proven routine schedule. The EPA suggests cleaning when there is visible mold, pests or excessive debris.
Do you use sanitizers or sealants?
Not by default. The EPA notes that their effectiveness in ducts is uncertain. We discuss any product with you first.
Should the furnace be cleaned at the same time?
The EPA recommends cleaning all system components if ducts are cleaned. We coordinate with your HVAC contractor on equipment they service.
How long does duct cleaning take?
It depends on the size of the home, how many registers and returns it has and the amount of debris. We give you an idea of scope after the assessment.
Tell us what you're seeing
Send a short description and a photo if you can. A team member will contact you to confirm a time.