"How often should you have air duct cleaning done?" is one of the most common questions homeowners ask, and the most common answer online is a tidy number: every three to five years. It sounds official, and it is often credited to the National Air Duct Cleaners Association (NADCA). But when we checked NADCA's own consumer pages and the U.S. Environmental Protection Agency's guidance in October 2026, neither gave a fixed schedule. This article explains what each one actually says, where the number may have come from, and a practical way to decide.
What EPA says: only as needed
EPA's consumer page, "Should You Have the Air Ducts in Your Home Cleaned?" (last updated February 19, 2026), takes the most conservative view: "EPA does not recommend that air ducts be cleaned except on an as-needed basis because of the continuing uncertainty about the benefits of duct cleaning under most circumstances."
EPA goes further and tells homeowners not to hire "duct cleaners who recommend duct cleaning as a routine part of your heating and cooling system maintenance." In EPA's view, the right frequency is not a number of years. It is when one of these conditions shows up:
- "Substantial visible mold growth inside hard surface (e.g., sheet metal) ducts or on other components of your heating and cooling system."
- Ducts "infested with vermin, e.g. (rodents or insects)."
- Ducts "clogged with excessive amounts of dust and debris and/or particles are actually released into the home from your supply registers."
The one thing EPA does recommend on a schedule is not duct cleaning. It is having fuel-burning furnaces, stoves and fireplaces "inspected for proper functioning and serviced before each heating season to protect against carbon monoxide poisoning."
What NADCA says: it depends on several factors
NADCA is the trade association for duct cleaning companies, so you might expect it to push a short interval. Its current consumer FAQ (on BreathingClean.com) does not. It says: "Frequency of cleaning depends on several factors, not the least of which is the preference of the homeowner."
NADCA then lists conditions that may call for cleaning more often:
- "smokers in the household"
- "pets that shed high amounts of hair and dander"
- "water contamination or damage to the home or HVAC system"
- "residents with allergies or asthma"
- "after home renovations or remodeling"
- "prior to occupancy of a new home"
NADCA's list is about situations, not years. Note that the allergy item is a reason NADCA gives for considering a cleaning. It is not a promise of relief. EPA says duct cleaning "has never been shown to actually prevent health problems," so anyone with symptoms should talk to a doctor. For more on that, see air duct cleaning for allergies and pets.
Where does "every 3–5 years" come from?
We looked for the 3–5 year figure on nadca.com and on NADCA's consumer site, BreathingClean.com, and did not find it there. It does appear widely in secondary sources: news and cost-guide articles and many company websites, often with NADCA's name attached. Some company FAQs give other numbers, such as every two to three years. One secondary summary of an older (2006) edition of NADCA's industry standard reportedly suggested inspecting air handlers yearly and ducts every two years, and cleaning if they were found dirty. That is an inspection interval, not a cleaning interval, and it is not current consumer guidance.
We are not saying no one at NADCA has ever used the phrase. We are saying it is not what NADCA's consumer guidance says today, so treat "NADCA says every 3–5 years" as unverified. When a company leads with a fixed schedule, it is fair to ask what in your particular system makes it due.
So how often should you have your ducts cleaned?
Put EPA and NADCA together and you get a sensible approach: check regularly, clean when there is a reason.
Check every year
- Change or check your furnace filter on the schedule the filter maker and your system call for. A clogged filter is the easiest problem to fix.
- Have the furnace inspected and serviced before heating season, as EPA recommends.
- Pull a supply register and look inside with a flashlight. Look for thick, matted debris, droppings or anything that looks like mold. EPA notes "it is normal for the return registers to get dusty," so a light film on a return grille is not a red flag.
- Notice whether dust actually puffs out of supply registers when the blower starts, or whether there is a musty smell when the system runs.
Consider a cleaning when
- One of EPA's three triggers is present.
- One of NADCA's situations applies: a remodel that put drywall dust into the system, water damage, a new-to-you home, a heavy-shedding pet or a smoker in the house.
- An HVAC technician servicing the furnace shows you contamination in the blower, coil or duct. EPA tells homeowners to ask any provider to "show you the contamination that would justify having your ducts cleaned."
Reno conditions: more reasons to check, not a shorter schedule
The Truckee Meadows is a dry, windy high desert. NOAA's 1991–2020 normals for Reno-Tahoe International Airport show just 7.35 inches of precipitation a year, and spring is the windiest season. Dust storms off the Black Rock Desert and Carson Sink have reached the Reno area, and wildfire smoke has blanketed the valley in several recent summers. The furnace also carries most of the load here, with about 4,669 heating degree days a year against 1,038 cooling degree days.
None of that sets a cleaning interval. It does mean filters may load up faster and a yearly look inside your system is worth the five minutes. After a heavy smoke season, follow the filter advice in our wildfire smoke and HVAC guide first. If smoke odor or ash persists after filter changes, some homeowners have their system inspected.
Signs you may be due (and signs you are not)
| Worth a closer look | Usually not a reason on its own |
|---|---|
| Visible mold in sheet-metal ducts or on the coil | Light dust on return grilles |
| Droppings, nesting material or insects in ducts | "It has been five years" |
| Dust blowing out of supply registers | A mailer or phone call offering a special |
| Recent remodel, water damage or moving into a home | A promise of allergy relief |
What a cleaning costs when it is due
EPA and NADCA put typical whole-system cleaning at $450 to $1,000 per system. Cost guides report averages of about $389 (HomeAdvisor, 2026) to $500 (Fixr, 2026). Those are estimates, not quotes. Our air duct cleaning cost guide has per-vent and Reno vent-count ranges. If an offer is far below those numbers, read how to spot a $99 duct cleaning scam before you book.
Before you hire anyone
EPA recommends talking to at least three providers and getting written estimates, plus "a written agreement outlining the total cost and scope of the job before work begins." Nevada requires contractors to show their license number in their ads, so check any company on the NSCB license search before you hire. If you want a second opinion on whether your system is due at all, start with is air duct cleaning worth it?
Reno Air Duct Cleaning is a free referral service. We connect Reno-area homeowners with independent local duct cleaning and HVAC companies for free, no-obligation quotes. We don't do the work ourselves. Whichever company you talk to, check its license on the Nevada State Contractors Board (NSCB) license search before you hire.
When you have a real reason to clean, you can get free quotes from local companies and compare. You can also read how a thorough job works on our air duct cleaning page.