BBB Tip: Cleaning your air ducts

Tip: Cleaning your air ducts

Man inspecting air duct

Don’t fall for paying hundreds or even thousands of dollars for air duct cleaning you don’t need. There are no set guidelines for when you should clean your ducts because what we know about benefits and problems is limited.  Every home is different, so it’s hard to generalize about whether you should clean your ducts without knowing more details.  There are no duct cleaning standards to certify, endorse or approve air duct cleaning companies set by the Environmental Protection Agency (EPA) or the Canada Mortgage and Housing Corporation (CMHC).

According to the EPA, there is no proof that cleaning your air ducts will prevent health problems. They say you should clean your ducts as needed, not as part of a routine. Look for these signs that it’s time for a cleaning:

  • Visible mold growth inside hard surface ducts or on other parts of your heating and cooling system
  • Ducts infested with vermin
  • Ducts clogged with large amounts of dust and debris
  • Particles entering your home from your supply registers

Some contractors may suggest chemical treatment for mold. Make sure you know the pros and cons before deciding if this is right for you.  Ask the company to show you proof of mold or other contamination. Something may look like mold, but only an expert will know for sure and may need lab tests to do so. For about $50 some labs can tell you if a sample on a clear strip of sticky household tape is mold or not.  If you go with the chemical treatment, you and your pets may want to leave the house while your ducts are treated.

The National Air Duct Cleaners Association (NADCA) says dusty registers are not automatically a problem as this is a normal result of dusty air going through them.  You can vacuum or wipe your registers with a damp cloth to clean them.

NADCA says people should think about these factors when deciding if they should have their ducts cleaned: 

  • The preferences of the homeowner
  • If there are smokers or pets that shed large amounts of hair and dander in the home
  • If cutting down on the indoor air pollutants will help people with allergies or asthma
  • If there has been water damage or renovations to the home or system

BBB suggests asking the company if they have worked on systems like yours before you sign a contract with them.  You should be suspicious of promises about the health benefits of duct cleaning without proof and be wary of companies that suggest cleaning as a routine part of maintenance. Avoid “blow-and-go” companies who charge a low fee and then do a poor job.  This can be worse than no cleaning at all because it can kick up particles or damage your system. Homeowners should expect to pay $450 - $1000 depending on the size of your system, how hard it is to get to it, climate and level of contamination.

Related things to remember: 

  • Cleaning your system may improve its efficiency and extend its life and may result in some energy and maintenance cost savings.
  • Fuel burning furnaces, stoves, or fireplaces should be inspected and serviced before each heating season to protect against carbon monoxide poisoning.

Remember to check out any air duct cleaner at before signing a contract.

Last Reviewed:  February 21, 2017