Direct answer
This is our reference list of duct cleaning figures that can be traced to a named source with a date. Each entry states the figure, who published it, when, what it actually measures, and how strongly it is supported. Several widely repeated numbers are weaker than they look, including the U.S. Environmental Protection Agency (EPA) cost range, which has not changed since at least January 2021. The page also covers what NIH and the one peer-reviewed review say, and the filtration figures. The last section lists claims we could not verify and therefore do not publish.
How to read this page
Every figure below carries an evidence label. The labels are not decoration; they are the difference between a number you can plan around and a number you should treat as one publisher’s assertion. Ten are in use across the site and all ten are defined here, including the three added on 15 August 2026 for allegations that have not been proven, for figures our own model produced, and for the cases where sources genuinely disagree.
This page is the machine-readable half of our reference section: figures, sources, dates. The human-readable half is the index of everything we publish, which groups the same material by the question it answers rather than by the number it contains.
| Label | Meaning |
|---|---|
| Verified fact | A statement of position or a documented outcome from a government body, court record, or standards organization. Not an estimate. |
| Typical range | A price range published by multiple independent sources that agree within a reasonable band. |
| Editorial estimate | Our own judgment, built from sourced inputs, and identified as ours. |
| Example calculation | An example calculation, worked from figures shown on the page. Arithmetic, not a market observation. |
| Industry guidance | Guidance from a trade association. Useful, but produced by the industry being described. |
| Editorial assessment | Our reading of what a body of evidence means, as distinct from the evidence itself. You can accept the sources and still reject the assessment. |
| Single source | One published source only. We report it and label it rather than laundering it into a consensus. |
| Alleged, not proven | An allegation in a complaint or filing that has not been proven or admitted. Common in enforcement material, where the charge is documented but the finding is not yet made. |
| Modeled estimate | An output of our own model rather than a published figure, such as a calculator result. The assumptions behind it are published in the methodology. |
| Sources disagree | Sources disagree, and the disagreement is the finding. We show the spread instead of averaging it into a single number that nobody published. |
EPA positions on duct cleaning
EPA’s consumer guidance was first published in October 1997 as EPA 402-K-97-002 and the page was last updated on February 19, 2026. It remains the only substantial federal treatment of residential duct cleaning we located, and it is the anchor for most of this site.
| Position | Why it matters | Evidence |
|---|---|---|
| “EPA does not recommend that air ducts be cleaned routinely, but only as needed.” | The federal position is not a schedule. Any annual or biennial cleaning interval you are quoted comes from a seller, not from EPA. | Verified fact |
| Duct cleaning has never been shown to prevent health problems | This applies to the entire service category, including careful work by certified firms. It is not a statement about bad operators only. | Verified fact |
| No evidence that light household dust in ducts poses a health risk | Removes the most common reason homeowners give for booking the service. | Verified fact |
| Studies do not conclusively show particle levels rise from dirty ducts or fall after cleaning | Much duct dust adheres to duct surfaces and does not necessarily enter living space. | Verified fact |
| Three conditions warrant consideration: substantial visible mold in hard-surface ducts or on components; vermin infestation; excessive debris being released from supply registers | This is the operative decision rule. EPA adds that underlying causes must be corrected or the problem recurs. | Verified fact |
| Visual inspection is how you decide | If inspection shows no large deposits of dust or mold, cleaning is probably unnecessary. Dusty return registers alone are normal. | Verified fact |
| Visual inspection alone cannot confirm mold; laboratory confirmation costs about $50 | Makes a technician’s on-the-spot mold diagnosis checkable for a small sum before you authorize anything. | Verified fact |
| Wet or moldy duct insulation cannot be effectively cleaned and should be removed and replaced | Once fiberglass liner is contaminated, cleaning does not prevent regrowth. This is a replacement decision, not a cleaning decision. | Verified fact |
| Condensation on cooling coils is a major factor in moisture contamination | Points the investigation at the evaporator coil rather than the duct runs. | Verified fact |
| Steam cleaning and other moisture-introducing methods should never be used on ductwork | A concrete disqualifier for a method a homeowner might be offered. | Verified fact |
Source for all of the above: EPA, Should You Have the Air Ducts in Your Home Cleaned?, page last updated February 19, 2026.
Beyond EPA: NIH, and the one peer-reviewed review
EPA is the anchor because it is the only substantial federal treatment written for homeowners. It is not the only source, and on the central question a second federal health office is blunter than EPA is, while the peer-reviewed literature contains exactly one review of the evidence.
| Statement | What it settles, and its limits | Source and date |
|---|---|---|
| Duct cleaning “should only be undertaken as a last resort, after other measures have been exhausted.” | The plainest sentence any federal body has published on this service, and stronger wording than EPA’s “only as needed.” Its scope is institutional: the fact sheet is guidance for NIH’s own laboratories and offices, not for houses. | NIH, Office of Research Services, Division of Occupational Health and Safety, DOHS Fact Sheet on HVAC Duct Cleaning, 05/2015 Verified fact |
| The evidence is still not sufficient to draw solid conclusions about duct cleaning’s benefits for indoor air quality, occupant health, HVAC system performance, or energy savings | Four claims dismissed in one sentence. EPA’s consumer guidance addresses health and particle levels; it does not take up system performance or energy savings at all. | NIH DOHS fact sheet, 05/2015 Verified fact |
| Prevention of duct contamination is what the fact sheet emphasizes | Its listed measures: routine HVAC maintenance to the manufacturer’s guidelines, sealing ductwork during renovation work, keeping occupied spaces clean, locating air intakes away from contaminant sources, regular visual inspection, and inspecting new ductwork before installation. | NIH DOHS fact sheet, 05/2015 Verified fact |
| NIH lists five conditions warranting cleaning, not EPA’s three | Persistent or permanent water damage in ducts; slime or microbial growth observed in ducts; debris restricting airflow; dust discharging from supply diffusers; offensive odors from ductwork or HVAC components. Attribute this list to NIH DOHS, never to EPA: it adds water damage and odors to EPA’s three. | NIH DOHS fact sheet, 05/2015 Verified fact |
| “no field studies have correlated poor IAQ with duct contamination” | The research-side counterpart to EPA’s position that studies are not conclusive. Controlled experiments do show that resuspended contaminants can raise indoor exposure; field studies have not linked duct contamination to poor indoor air quality. | Zuraimi, MS, Is ventilation duct cleaning useful? A review of the scientific evidence, Indoor Air 20(6), 2010, pp. 445–457 Single source |
| Post-cleaning air pollutant concentrations can be higher than pre-cleaning levels | Removal efficiency inside the ducts can be high while the effect on indoor air varies widely, and the direction is not guaranteed. Stronger than the 2001 eight-home study, which found levels raised during cleaning rather than after it. | Zuraimi (2010), abstract via the National Research Council Canada record Single source |
| Inadequate evidence that duct cleaning improves duct airflow or reduces energy consumption; insufficient evidence that it relieves occupants’ symptoms | Covers three of the advertised benefits at once, from inside the peer-reviewed literature rather than from agency guidance. | Zuraimi (2010) Single source |
How far the Zuraimi review can be pushed, and no further
It is one paper. It is a narrative review of the literature, not a systematic review and not a meta-analysis, and we do not describe it as either. We read the abstract only; the full text is not open access. It was published in 2010, which makes it sixteen years old. And we attribute no study count to it, because the abstract does not give one.
What it is: a peer-reviewed paper in Indoor Air, cited by the NIH fact sheet above and indexed in EPA’s own HERO bibliographic database. Note also that the two catalogue records disagree on its page range — EPA’s HERO record gives 445–457, the National Research Council Canada record gives 445–447 and lists the author as Sultan, Z. M. Same person, same paper.
The EPA cost figure, and why we date-stamp it every time
A stale number wearing a fresh date
EPA states that duct cleaning services typically, though not always, range from $450 to $1,000 per heating and cooling system. That sentence is also present, word for word, in the January 2021 archived snapshot of the same page. The figure is therefore at least five years old and has never been inflation-adjusted. The “last updated February 19, 2026” stamp on the live page refers to the page, not to the number.
We disclose this every time we cite the range. At least seven publications reproduce $450–$1,000 without noting its age, which makes it look like seven corroborating sources when it is one.
Cost figures, with support levels
| Figure | What it measures | Source and date | Support |
|---|---|---|---|
| $25–$50 per supply vent, about $35 modal | The consumer-facing pricing unit used in most advertising. Multiply by your register count for a first approximation. | Appears independently in Angi (updated August 3, 2026), HomeAdvisor (June 20, 2026), Fixr (January 29, 2026), This Old House (April 9, 2026), Forbes Home (June 6, 2025) and others | Typical range Best-supported number in the corpus |
| $40–$75 per return vent | Returns are priced above supply openings because they are larger and fewer. | This Old House, April 9, 2026; Fixr, January 29, 2026 (returns to $75) | Typical range Two sources |
| $0.15–$0.30 per square foot, up to $0.40 on large or difficult jobs | An alternative pricing basis, and the arithmetic behind most published home-size tables. | Angi, HomeAdvisor, NerdWallet (April 22, 2026), HomeGuide (October 24, 2025), This Old House, Fixr | Typical range Four or more sources |
| $90–$150 per technician-hour | Contractor-side labor cost, used mainly for unusual or heavily contaminated jobs. | Housecall Pro, January 30, 2026, a trade source writing for contractors | Typical range |
| $389 national average, $271–$509 typical | What homeowners reported paying for a typical single-system job, not a quote you should expect. | Angi, updated August 3, 2026, and HomeAdvisor, June 20, 2026 | Single source Five publications, one dataset |
| $450–$1,000 per heating and cooling system | A per-system quote range for a full-scope cleaning including the air handler, coils, and blower. | EPA, figure unchanged since at least January 2021; repeated by NADCA and others | Single source Many citations, one origin, and it is stale |
| $300–$700 for a single-system home | A practical planning range that sits between what homeowners report paying and what full-scope quotes ask. | Fixr, January 29, 2026 ($500 at 2,000 sq ft) | Typical range Directly sourced; bracketed above and below by other lineages |
| $300–$800 for a 2,000 sq ft home | The one home-size row where every source that publishes a table lands in the same band. | Angi $300–$600; Fixr $300–$700; This Old House $300–$800; HomeGuide $400–$800 | Typical range Four sources, though all derived from square-foot rates rather than survey data |
| $100–$200 for a standalone dryer vent cleaning, roughly $40–$100 bundled | An add-on for a separate duct with a separate, fire-safety rationale. | Multiple cost publications listed in our source table | Typical range |
| $75–$250 for a sanitizing or antimicrobial add-on | The most commonly upsold line item. Read the EPA registration facts below before agreeing to it. | Forbes Home $75–$150; Housecall Pro $75–$200; one further publication to $250 | Typical range Three sources |
| $200 minimum service fee | The floor some companies apply regardless of vent count. | Forbes Home, June 6, 2025 | Single source One source only |
| Two systems $650–$1,000; three or more $1,000–$1,500+ | Multi-system pricing tiers. Note the second system adds well under double. | Housecall Pro, January 30, 2026 | Single source One source only |
| About $50 for laboratory confirmation of mold | The cost of checking a technician’s mold claim independently. The most useful $50 on this page. | EPA | Verified fact |
Fifteen publications, about three origins
The most consequential thing we found is not a number. It is that the apparent consensus on duct cleaning prices is manufactured by repetition.
| Lineage | Figures | Publications carrying it | What it really measures |
|---|---|---|---|
| A — Angi / HomeAdvisor project data | $389 average, $271–$509 typical | Five: Angi, HomeAdvisor, NerdWallet, which attributes it openly to Angi, Today’s Homeowner at $388, and Bob Vila | Reported homeowner spend on a typical single-system job. Angi owns HomeAdvisor, so the two are one dataset. |
| B — EPA’s per-system range | $450–$1,000 per system | Eight, counting EPA itself: EPA, NADCA, This Old House, HomeGuide, Modernize, Inch Calculator, HVAC.com, with Forbes Home matching it | A quote range for full-scope cleaning including air handler, coils, and blower. Unchanged since at least January 2021. |
| C — genuinely independent | Fixr $300–$700; Housecall Pro $400–$1,000, built from $90–$150 per technician-hour and a 20–40% margin | Two | Both land between A and B, which is the strongest reason to trust the middle of the range. |
The gap between lineage A and lineage B is definitional, not empirical. Editorial assessment They are pricing different products: A reports what people paid for a typical job, B quotes a full-system scope. Presenting them as a disagreement about market price misses what is actually going on, and presenting either as corroborated by the outlets that reprint it is worse.
The vent-count table is arithmetic, not data
The widely reproduced table showing 8 vents at $200–$400, 12 at $300–$600, 16 at $400–$800, and 20 at $500–$1,000 is nothing more than vent count multiplied by $25–$50. It appears in several places and looks like four independent datasets agreeing. It is one multiplication. We never present it as corroboration.
Enforcement figures
These come from attorney general offices, court filings, and Better Business Bureau (BBB) studies. They are the most solid facts on this page, because they are records of proceedings rather than estimates.
| Figure | Case and context | Source and date |
|---|---|---|
| $10 million in penalties | Washington State’s case against US Air Ducts, Sky Builders, and DLM Services, which also produced a permanent injunction. The pricing deception rode alongside telemarketing violations, which were the easier legal hook. | Washington State Attorney General, August 26, 2020 Verified fact |
| More than 13 million robocalls to over 1 million Washingtonians; one consumer received 169 calls | Caller-ID spoofing used more than 100 numbers and local-sounding names. Roughly 100 fake five-star reviews were posted in a single week. | Washington State Attorney General, September 24, 2019 Verified fact |
| Advertised $29–$55; charges often exceeded $1,000 | Coupons cited a “regular” price of $150–$225 that the company never charged. Ads omitted that only half the heating and cooling system was included. Roughly $1,200 “VIP memberships” guaranteed only annual visual inspections. | Washington State Attorney General filings, 2019–2020 Verified fact |
| The same UV light sold for $40 to one customer and $775 to another; sanitizing spray billed from $1 to over $300 | Oregon’s complaint against the same operators. Technicians were given “a general range to charge.” Wildly variable pricing for identical work is the clearest evidentiary marker separating aggressive selling from fraud. | Oregon Department of Justice complaint, filed October 16, 2019 Verified fact |
| $1.71 million in civil penalties, plus $68,157.36 in restitution | New Jersey’s action against United Air Care and Indoor Air Care over coupons advertising $37.95–$69.95 “Whole Duct House Cleaning” used to bait buyers toward higher-priced services. The contractors were unregistered. | New Jersey Division of Consumer Affairs, April 5, 2011 Verified fact |
| A 40-page complaint alleging mold contamination that the state says did not exist | Illinois against Warranty USA Inc., trading as Air Duct Cleaning Pros, and its president Moshe Kesem, in the Circuit Court of Cook County. The state alleged customers were told their ducts and heating systems held mold contamination requiring expensive work. The filing date is January 11, 2011. The 2018 date attached to this case elsewhere online is the posting date of a campaign-site copy of the announcement, not the date of the action, and repeating it is a seven-year error. A case number appears in the HarrisMartin report in a form Cook County’s numbering does not use, so we cite the court and the date. No judgment, settlement, or dismissal was located: these remain allegations. The further allegation that fabricated photographs of mold damage were shown to customers appears only in the Attorney General’s own announcement and is carried on this site as single-sourced. Alleged, not proven | HarrisMartin Publishing litigation report, February 24, 2011, on a case filed January 11, 2011 Verified fact |
| More than 230 complaints; advertised $35, charged up to $1,000 | Colorado’s action against Seabreeze Air, Quality Air, and Fresh Air, which produced a temporary restraining order. The case also documented phoenixing: telling courts the business had closed, then reopening under new names. | CBS News Colorado, reporting the Colorado Attorney General action, November 25, 2013 Verified fact |
| $916,000 ordered, reduced to $150,000 if paid, plus a permanent ban on advertising or performing air-duct cleaning services in Colorado | The final resolution of the same Colorado matter, against Andre Shatyko and Alexander Kurdyukov, trading as Seabreeze Air LLC, Quality Air, and Fresh Air LLC. The ban on the individuals is the part that answers the phoenixing. Note the sourcing: the outlet dates its story November 24, 2024 while the underlying action is the 2013 case, so we cite the penalty and the ban and assert no judgment date. | Legal Newsline, story dated November 24, 2024 Single source |
| 62 companies studied; 21 asked to change their advertising; 18 complied, 3 refused and received F ratings | A BBB Denver study of duct cleaning advertising. One company advertised a $242 “whole house air duct and carpet cleaning” whose fine print limited it to five rooms and ten vents; the owner conceded it was not the whole house. Note what this study is: a third of a local industry with defective advertising and no allegation of fraud. | CBS News Colorado, reporting the BBB Denver study, February 27, 2013 Verified fact |
| $49 advertised specials; bills of $1,799, $2,700, $2,780, and $3,000 | A BBB St. Louis warning. An 81-year-old customer was charged $1,799. Technicians “discovered” mold, bacteria, or furnace problems and pressed for immediate purchase. | BBB St. Louis warning, reported November 2011 Verified fact |
| A $39 duct and $99 furnace advertisement that produced a $1,250 bill | One of two customers in a television investigation; the other paid $1,794 for a “VIP” package after responding to a $39 advertisement. Both describe pressure applied in the home. | KGW investigation Verified fact |
| $298 advertised, $399 invoiced, with no license the state could identify | A Fargo case in which the heating system failed days after the work. North Dakota and Minnesota Secretary of State and attorney general offices could not identify the business as licensed. | Valley News Live, January 7, 2025 Verified fact |
One correction to a claim we see everywhere
Duct cleaning telemarketing has been prosecuted by state attorneys general, and a duct cleaning case appeared in the nationwide robocall sweep the Federal Trade Commission (FTC) coordinated in June 2019 as Operation Call It Quits. But that entry was the Michigan Attorney General’s state action. The FTC’s own seven actions in that sweep covered credit cards, money-making schemes, autodialers, solar leads, medical alerts, smoking cessation, and debt relief. None found is the accurate summary of our own search for an FTC enforcement action against a duct cleaning company: we looked and did not find one, which is not the same as establishing that none exists.
State licensing: zero for eight
We read the contractor licensing rules of eight states, going to the statute or the state agency’s own classification list rather than to trade commentary. None of the eight licenses air duct cleaning as a distinct trade. Verified fact The sample is deliberately hostile to that conclusion: Hawaii publishes 68 specialty classifications and California 47, and the trade appears in neither list. Eight states are not fifty, and we did not examine city or county licensing at all, so this is reported as a named sample rather than as a national rule. None of it is legal advice; your own state agency is the authority on what applies to you.
| State | Duct cleaning classification? | What applies instead | Source |
|---|---|---|---|
| California | None | C-20 warm-air heating, ventilating and air-conditioning covers ducts, registers, flues and filters as part of HVAC systems. A licensing threshold applies at $1,000 in aggregate. | Contractors State License Board classifications and its description of classifications Verified fact |
| Florida | None, but the statute names the work | Several licensed contractor categories are defined to include duct cleaning and equipment sanitizing that “requires at least a partial disassembling of the system.” The qualifier is the whole point: this is a conditional scope, not a duct cleaning license, and it is wrong to state that Florida requires a license to clean air ducts. | Fla. Stat. 489.105 Verified fact |
| Texas | None; Texas has no general contractor license | The air conditioning and refrigeration contractor license covers design, installation, repair, maintenance and service of environmental air conditioning equipment. Duct cleaning is not named. | Tex. Occ. Code ch. 1302 Verified fact |
| New Jersey | None | Home improvement contractor registration. The regulation’s list of covered work expressly includes central heating and air conditioning equipment, and the state’s 2011 action charged duct cleaning operators with failing to register. This is the only enforcement proof in the sample. | N.J.A.C. 13:45A-16.1A, N.J.S.A. 56:8-137 and the April 5, 2011 enforcement release Verified fact |
| Michigan | None among ten mechanical classifications | The ductwork classification covers air distribution arrangements for supply, return and exhaust, which is installation work rather than cleaning. | Michigan LARA mechanical contractor application Verified fact |
| Arizona | None | C-39 and CR-39 cover refrigeration, evaporative cooling, heating and ventilation with ductwork. A license is required where labor and materials exceed $1,000 or a permit is required. | Arizona Registrar of Contractors classifications Verified fact |
| Washington | None among the specialty codes | General or specialty contractor registration to bid, advertise and perform construction work. The nearest specialty code is SM, heating, ventilation, air-conditioning and refrigeration. The separately licensed trades do not include HVAC or cleaning. | Washington L&I contractor registration and application form F625-001-000 Verified fact |
| Hawaii | None across C-1 to C-68 | C-52 ventilating and air conditioning covers fabricating, assembling and installing complete systems. Cleaning is not a listed scope. With 68 specialty classifications this is the hardest test in the sample. | Hawaii specialty contractor classifications, title 18 ch. 237 exh. A Verified fact |
Mold work is the exception worth knowing, because it attaches to the upsell that runs through the enforcement record above.
| Provision | What it establishes | Source |
|---|---|---|
| Florida licenses mold assessment and mold remediation, and separates the two roles | An assessor may not remediate a structure they assessed within the previous 12 months, and a remediator may not assess one they remediated in that window. Neither may accept referral compensation from the other. Violations escalate to a third-degree felony on a third or subsequent offense. | Fla. Stat. 468.8419 Verified fact |
| Florida exempts some people from those requirements | Exemptions include persons acting within the scope of a chapter 489 contractor license, though the exemption is lost if they hold themselves out to the public as a certified, registered, licensed or professional mold assessor. | Fla. Stat. 468.841 Verified fact |
| Texas licenses mold assessment and remediation, and defines remediation to include cleaning | Mold remediation covers the removal, cleaning, sanitizing, demolition or other treatment of mold or mold-contaminated matter. Exemptions include work under 25 contiguous square feet, supervised employees, and some owner-occupied residential situations. | Tex. Occ. Code ch. 1958 Verified fact |
Because those exemptions are real and broad, the only defensible use of this material is as a question a homeowner can ask — who is licensed to make the mold finding, and may the same firm sell the remedy — rather than as a suggestion that any company selling mold work is acting unlawfully.
Job duration: one figure exists, and it is from 2008
This is the shortest section on the page because the published record is nearly empty. No federal agency and no standards body states how long a residential duct cleaning should take.
| Figure or finding | What it means | Source and date |
|---|---|---|
| A quality job takes two technicians about 8 to 15 hours | The only duration figure we located from a reputable, non-commercial consumer-research organization. It is a single source and it is eighteen years old, so we cite it with its date every time and never as a current benchmark. The same article attributed a $400 to $1,000 price to NADCA in 2008, against $450 to $1,000 today, which is roughly 12 percent of movement in eighteen years and supports the view that the headline range is a convention rather than a measurement. | Consumer Reports, February 4, 2008 Single source |
| NADCA publishes no time estimate | Its page is titled “Cost & Time Estimates” and gives a price range, then says duration varies with home size, number of systems, accessibility, contamination level and technician count, and defers to the individual contractor. The industry’s own trade association will not commit to a number. | NADCA, undated Industry guidance |
| The ACR standard specifies an outcome, not a duration | ACR, The NADCA Standard, 2025 Edition, defines cleanliness levels and verification, including a vacuum test. It sets no time requirement, so hours on site prove nothing against the industry standard in either direction. | ACR, The NADCA Standard, 2025 Edition Industry guidance |
| EPA gives no figure and tells the homeowner to demand one | Its only duration-adjacent instruction is that a homeowner billed hourly should request an estimate of the number of hours or days the job will take, and ask whether the work will be interrupted. The phrase “hours or days” is EPA’s. | EPA duct cleaning guidance, updated February 19, 2026 Verified fact |
| No agency or standards body publishes a duration at all | Checked: EPA, the Department of Energy, the Consumer Product Safety Commission, the Centers for Disease Control and Prevention, the National Institute for Occupational Safety and Health, NADCA and ACR, ASHRAE, SMACNA and NAIMA. The widely circulated “3 to 5 hours” traces only to contractor marketing pages, so we do not repeat it. | Our source review, August 15, 2026 Editorial assessment |
Biocide and sealant registration facts
These are regulatory facts rather than opinions, and they are the ones most likely to save a reader money at the moment a technician is standing in the hallway.
| Fact | Consequence | Source |
|---|---|---|
| A small number of products are registered by EPA specifically for use on the inside of bare sheet metal air ducts | Sanitizing bare sheet metal with a properly registered product is a legitimate, if narrow, category. It is not the general case. | EPA duct cleaning guidance Verified fact |
| No products are currently registered by EPA as biocides for use on fiberglass duct board or fiberglass-lined ducts | An antimicrobial fogging upsell on a fiberglass-lined system has no EPA-registered basis at all. | EPA duct cleaning guidance Verified fact |
| A “hard, non-porous surfaces” label claim does not include HVAC use unless HVAC use is specifically on the label | EPA warns that such use could lead to significant indoor exposures with potentially unreasonable adverse effects. | EPA disinfectants in HVAC guidance, updated July 17, 2026 Verified fact |
| Using a pesticide product inconsistently with its label directions violates federal law | The label is the legal document. You can ask to see it before anything is applied in your home. | EPA duct cleaning guidance Verified fact |
| Little research has been conducted on the effectiveness of most biocides and ozone inside ducts | Even where a product is registered, effectiveness in situ is not established. | EPA duct cleaning guidance Verified fact |
| EPA, NADCA, NAIMA, and SMACNA do not recommend routine use of sealants to encapsulate contaminants in any type of duct | Regulator and industry agree here, which is unusual and therefore worth weight. EPA adds that little is known about the toxicity of these products in typical use or if they catch fire. | EPA duct cleaning guidance Verified fact |
Filtration figures, where a specific number does exist
Duct cleaning has no published interval, no demonstrated benefit and a price figure that has not moved since at least 2021. Air filtration — the measure most often recommended in its place — has a named consensus test standard, an explicit EPA recommendation with a number in it, and federally funded field measurements of what that number costs. The contrast is the point of putting them on the same page.
| Figure or statement | What it means | Source and date |
|---|---|---|
| Select a filter rated “at least MERV 13 or as high as your system will accommodate.” | EPA’s actual filtration recommendation, and the most specific consumer instruction it gives anywhere near this subject. The second clause is a real constraint, not a hedge — see the two rows below. | EPA, Guide to Air Cleaners in the Home, page last updated February 17, 2026 Verified fact |
| Filters rated MERV 13 and above must demonstrate at least 50 percent removal efficiency for the smallest particles tested | What the number buys. The American Lung Association independently prefers MERV 13 or above for the same reason. | EPA, Guide to Air Cleaners in the Home, February 17, 2026 Verified fact |
| Most furnaces and HVAC systems accommodate a MERV 13 filter without equipment problems, provided the filter is replaced frequently | EPA’s own qualifier, with its condition attached. It adds that anyone wanting certainty should consult an HVAC technician. | EPA, Guide to Air Cleaners in the Home, February 17, 2026 Verified fact |
| MERV 10 to 13 filters changed energy use by less than 1 percent | Measured across a wide range of performance conditions and climates. This is why a MERV 13 upgrade is close to free in energy terms for most homes. | Walker, Dickerhoff, Faulkner and Turner, Lawrence Berkeley National Laboratory, System Effects of High Efficiency Filters in Homes, prepared for the U.S. Department of Energy, March 2013 Single source |
| MERV 16 filters were associated with potential energy increases above 5 percent and with usability problems | The risk in high-efficiency filtration lives at the top of the scale, not at MERV 13. In systems already close to their blower performance limits, a MERV 16 filter pushed the blowers to those limits. | LBNL for the Department of Energy, March 2013 Single source |
| About 188 cubic feet per minute, roughly 22 percent, of airflow lost in PSC-blower systems | Measured when a clean MERV 16 filter replaced a low-MERV one. Failure mode depends on the blower: older permanent split capacitor motors lose airflow as filters load, while newer brushless permanent magnet motors hold airflow and draw more power to do it. | LBNL for the Department of Energy, March 2013 Single source |
| MERV comes from testing under ANSI/ASHRAE Standard 52.2, current edition 2025 | Full title: Method of Testing General Ventilation Air-Cleaning Devices for Removal Efficiency by Particle Size. Its scope covers particles from 0.30 to 10 micrometers. We name the standard and its edition only: it is sold rather than published, and we have not read it, so we quote nothing from it. | ASHRAE standards listing; designation confirmed at the ANSI Webstore Verified fact |
| No agency states a universal filter replacement interval | The deferral is the rule: EPA’s operative instruction is to replace filters according to the manufacturer’s recommendations, noting that manufacturers typically say every 60 to 90 days. ENERGY STAR’s checklist says inspect, clean or change monthly — inspecting is not replacing. The Department of Energy says every month or two during the cooling season. A 2009 EPA and ENERGY STAR guide says at least every three months. The 30-, 60- and 90-day figures describe what manufacturers typically specify, not independent federal determinations. | EPA, February 17, 2026; ENERGY STAR, undated; DOE Energy Saver, undated; EPA 430-K-09-004, August 2009 Verified fact |
How far the filter study goes
The Lawrence Berkeley National Laboratory figures come from ten homes, monitored for a year, in California, in 2013, with results extended to other climates by simulation rather than measurement. The residential blower population has shifted toward brushless permanent magnet motors since. Cite it as what it is: a Department of Energy–funded field study of ten homes. It is the only measured evidence we found on the filtration tradeoff, and it is more evidence than exists for any claimed benefit of duct cleaning.
Two things nobody publishes, so neither do we: any table of pressure drop by MERV rating, and any crosswalk between MERV and the proprietary FPR and MPR scales used by some retailers and manufacturers. EPA names all three scales and converts none of them.
Industry guidance worth knowing
NADCA is a trade association rather than a regulator, so we label its guidance accordingly. Some of it is notably candid about its own industry.
- NADCA’s own cost guidance puts an average-sized home often between $450 and $1,000. Industry guidance That is the same figure as EPA’s, so it should not be counted as a second data point.
- NADCA warns homeowners to beware of “blow-and-go” air duct cleaning companies. Industry guidance
- NADCA lists being told mold is present without a proper inspection as a common red flag. Industry guidance EPA independently confirms that visual inspection alone cannot establish mold.
- NADCA cautions that extremely low-cost whole-house specials often cover only limited portions of the system and may exclude the air handler, blower fans, coils, registers, or the access openings the job requires. Industry guidance
- NADCA lists the factors that move price: number of systems, accessibility of ductwork and components, type of ductwork, level of contamination, and geographic location. Industry guidance Note that it gives directions, not dollar amounts.
- NADCA warns that some companies illegally use its logo or falsely claim membership. Industry guidance Verify directly with the association rather than trusting a logo on a van or a website.
What we could not verify
This section is not an admission of weakness. It is the part of the page other publications leave out, and it is where a reader most often gets misled. Everything below is something we looked for and did not find adequate support for. None of it appears as fact anywhere on this site.
| Claim | What we found instead |
|---|---|
| The “$99 whole house” scam special | Every instance traced back to competitor HVAC marketing blogs, never to a regulator, a BBB study, or a news investigation. Documented enforcement figures cluster at $29 to $69.95. We write “advertised specials as low as $29” and cite Washington State instead. |
| Fake before-and-after photographs | Half verified, and the halves matter. The Illinois case is real, dated January 11, 2011, and independently reported, and the allegation of invented mold contamination is corroborated. The specific claim that fabricated photographs were shown to customers appears only in the Attorney General’s own announcement of that case, republished on a former officeholder’s campaign site. We report it as single-sourced, never as established practice, and never dated to 2018. |
| That a particular state licenses air duct cleaners, so unlicensed competitors are operating illegally | Unverified where we tested it. The Michigan version of this claim traces to a duct cleaning company’s own marketing page; no state source supports it, and Michigan’s ductwork classification is an installation scope. Note the commercial interest, which is the same structural problem as the misattributed “five to eight hours” quote below. Every non-government answer we found to “do you need a license to clean air ducts” was industry marketing, lead generation, or a paid answer site. We cite statutes and state agency pages only. |
| Technicians planting debris in ducts | Found only in industry marketing writing. No government, court, or investigative source. We treat it as folklore. |
| Cash-only or unusual payment demands as a scam marker | No government, BBB, or NADCA source supports it. Omitted. |
| Refusing to let the homeowner watch as a red flag | Not documented as a scam pattern. EPA frames the same ground from the other direction, as the homeowner’s right to demand proof that the work was done. We use that framing. |
| FTC enforcement against duct cleaning companies | None found. See the note above. State attorneys general, not the FTC, have brought these cases. What we can report is the result of our own search, not the contents of the agency’s whole docket. |
| A price difference between flexible and rigid sheet metal duct | Direction is agreed on; no source publishes a dollar amount or a percentage. We publish no number. |
| A multiplier for poor duct accessibility | Same situation. Everyone says accessibility raises price; nobody quantifies it. Where our calculator applies an adjustment, it is disclosed as our assumption, not market data. |
| A surcharge for contamination severity, rodents, post-construction dust, or smoke | No quantified figure found in any source. |
| A duct-cleaning-specific mold surcharge | Does not exist in the published record. The “mold” figures that circulate range from $500 to $10,000 across eight publications, a twentyfold spread, because they are whole-house remediation prices rather than a duct cleaning add-on. We refuse to give a single tidy number for something that does not have one. |
| An authoritative typical minimum service charge | One publication gives $200. That is a single source and we label it as one. |
| An Architectural Digest duct cleaning cost page; current Consumer Reports duct cleaning cost data | Neither exists. Both are occasionally cited secondhand. We never cite them. The Consumer Reports material we do cite is a single article from February 2008, used for its duration figure and dated every time. |
| A regulator finding that jobs advertised at two to three hours actually require five to eight | Misattributed, including in our own drafts until pre-publication review on 15 August 2026 caught it. The statement comes from the general manager of a competing duct-cleaning company quoted by CBS Colorado in its November 25, 2013 report, not from any attorney general filing. It is a competitor’s estimate given to a reporter and carries the commercial interest that implies. Our corrections policy records the change. |
| Any duration figure broken out by home size, vent count, or number of systems | No source publishes one. The only size-linked number in the Consumer Reports article is a price scoped to a typical 2,000-square-foot house. We do not build that table. |
Sources we deliberately exclude
Some published pages are real but too old or too derivative to cite as current market data.
- Thumbtack, whose duct cleaning cost page is dated August 1, 2017 and gives a $250 average with a $125–$495 range. Nine years is too stale to present as current pricing.
- Bob Vila, dated November 2023, which carries an earlier vintage of the Angi series. Citing it alongside the current $389 figure would manufacture a second data point out of the same dataset.
- Inch Calculator, dated August 2023, which reproduces the EPA range.
What to do next
- The same figures assembled into a planning range — including why “$389” and “$450 to $1,000” describe different jobs rather than contradicting each other.
- Air duct cleaning scams — the enforcement record above, told as the patterns to recognize.
- Fact-checking policy — how a number gets onto this page, and what disqualifies one.
- Duct cleaning glossary — the terms these figures are measured in.