If you ultimately decide to have your ducts cleaned, here’s how to hire a responsible duct cleaner.
What to Avoid
Don’t hire a company that makes sweeping claims about health benefits or claims to be EPA-certified for duct cleaning: That agency offers no such certification.
Shop for a good price, but avoid companies that advertise specials under $200, or even under $100. Known in the industry as “blow-and-go” outfits, they will likely just hook up a vacuum to part of your duct system and do a poor job. Or use the low price as a bait-and-switch tactic.
What to Look For
Focus your search on contractors who belong to the National Air Duct Cleaners Association (NADCA), a nonprofit trade association. Ask for written proof of a company’s NADCA membership and certification, or use the NADCA website to locate members in your area. NADCA members must subscribe to the NADCA code of ethics. More important, they must employ at least one NADCA-trained-and-certified technician and employ NADCA-approved methods. Members must also carry at least $500,000 in general liability insurance.
Also consult our Consumer Trusted page and sponsors to consider companies that have received favorable recommendations and help the fight against fraudulent companies.
Get several companies to come to your home to perform inspections and provide estimates. Ask them to perform the inspection while you are present. Inspections might consist of only a flashlight and mirrors or involve inserting a video camera into the ducts. Ask them to show you the contamination that would justify having your ducts cleaned.
Confirm that the cleaning will cover the entire system. A cleaning should include supply ductwork, return ductwork, supply plenum (chamber), return plenum, and all registers and grilles. You may agree, for a reduced price, to exclude the blower fan assembly, heat exchangers, evaporator coils, and collector pans if those are serviced under a maintenance plan with a heating and air-conditioning contractor. But these are the elements most relevant to system efficiency and should be explicitly listed by the duct-cleaning company unless you have agreed to exclude them.
Before agreeing to any work, get written estimates after each inspection.
Get the company to agree in writing that it will perform all of the following (mostly drawn from the EPA’s duct-cleaning guidance document)—
- Open or create access ports or doors to allow the entire system to be cleaned and inspected.
- Inspect the system before cleaning to make sure there are no asbestos-containing materials (e.g., insulation, register boots, etc.) in the heating and cooling system. (Asbestos-containing materials require specialized procedures, and should be disturbed or removed only by specially trained and equipped contractors.)
- Follow NADCA guidelines in attaching some sort of vacuum device to the system during cleaning to remove loosened particles. (NADCA does not endorse one type of equipment or another. Truck-mounted equipment is typically more powerful and ensures that loosened particles are sucked outside the home. Portable equipment can be located nearer the work site.)
- Use vacuum equipment that exhausts particles outside of the home or, if the vacuum exhausts inside the home, use only vacuuming equipment with high-efficiency particle air (HEPA) filters.
- Protect carpet and household furnishings during cleaning.
- Use well-controlled brushing of duct surfaces in conjunction with contact vacuum cleaning to dislodge dust and other particles.
- Use only soft-bristled brushes for fiberglass duct board and sheet metal ducts lined internally with fiberglass. (Although flex duct can also be cleaned using soft-bristled brushes, it can be more economical to replace accessible flex duct.)
- Take care to protect the ductwork, including sealing and reinsulating any access holes that have been made or used to make them airtight.
- Follow NADCA standards for air-duct cleaning and North American Insulation Manufacturers Association recommended practices for ducts containing fiberglass lining or constructed of fiberglass duct board.