Is Air Duct Cleaning Worth It? What the EPA Actually Says

Sometimes. Air duct cleaning is worth it when there is a specific problem: substantial visible mold, rodents or insects in the ducts, or ducts clogged with so much dust and debris that particles blow out of the supply registers. Without one of those, the U.S. Environmental Protection Agency (EPA) says cleaning is probably unnecessary, and it does not recommend cleaning on a routine schedule.

Here's what to expect in this guide:

• What the EPA says about duct cleaning, in its own words
• What the evidence shows for health, dust and energy bills
• When duct cleaning is worth the money, and when it isn't
• What changes after a remodel, in a new home or in a rental
• How to avoid paying for a cleaning you don't need

What Does the EPA Actually Say About Duct Cleaning?

Clean when there is a reason, not on a schedule. The EPA's guide for homeowners says it "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."

The EPA doesn't say cleaning is harmful, either: "Provided that the cleaning is done properly, no evidence suggests that such cleaning would be detrimental." Its summary is that "a blanket recommendation cannot be offered." The guide was first published in October 1997, and it is still the guidance the EPA publishes today.

Does Duct Cleaning Help With Health, Dust or Energy Bills?

The evidence is thin on all three. Here is what the EPA says about each.

• Health: "Duct cleaning has never been shown to actually prevent health problems." On whether it does, the EPA's answer is, "The bottom line is: no one knows." It adds that "there is no evidence that a light amount of household dust or other particulate matter in air ducts poses any risk to health."
• Dust: Studies don't conclusively show that dust levels in homes rise because of dirty ducts or fall after cleaning. The EPA's reason: "much of the dirt that may accumulate inside air ducts adheres to duct surfaces and does not necessarily enter the living space."
• Energy bills: "Little evidence exists to indicate that simply cleaning the duct system will increase your system's efficiency." The EPA does note that "some research also suggests that cleaning dirty cooling coils, fans and heat exchangers can improve the efficiency of heating and cooling systems." That is about the equipment, not the ducts alone.

When Is Duct Cleaning Worth the Money?

When you can see the problem. The EPA says you should consider having your ducts cleaned in three situations:

• Mold: there is substantial visible mold growth inside hard surface (such as sheet metal) ducts or on other components of your heating and cooling system.
• Pests: ducts are infested with rodents or insects.
• Heavy debris: ducts are clogged with excessive amounts of dust and debris, or particles are actually released into the home from your supply registers.

Two cautions from the EPA apply to all three. First, fix the cause: before any cleaning, the cause or causes "must be corrected or else the problem will likely recur." Second, be sure it is mold. Ask the service provider to show you any mold they say exists, because a positive determination "can be made only by an expert and may require laboratory analysis for final confirmation."

If you suspect mold in the system, the EPA's mold guide says: "Do not run the HVAC system if you know or suspect that it is contaminated with mold - it could spread mold throughout the building." A mold or water problem may also need an HVAC technician or a plumber to fix the source.

When Is Duct Cleaning Not Worth It?

When nobody has symptoms and the ducts look fine. The EPA says that if no one in your household suffers from allergies or unexplained symptoms or illnesses, and you see no indication of "large deposits of dust or mold (no musty odor or visible mold growth)," having your ducts cleaned "is probably unnecessary."

These are not reasons by themselves:

• A dusty return grille. The EPA says it is normal for return registers to get dusty, and the registers "can be easily vacuumed or removed and cleaned."
• A little dust inside the ducts. "A light amount of household dust in your air ducts is normal."
• The calendar. Duct cleaning "is not considered to be a necessary part of yearly maintenance," which the EPA describes as regular filter changes, regular cleaning of drain pans and coils, and yearly inspections of heating equipment.

If family members have unusual or unexplained symptoms that you think might be related to your home, the EPA's advice isn't a cleaning. It says "you should discuss the situation with your doctor." For more on timing, see our guide on how often to clean air ducts.

Is Duct Cleaning Worth It After a Renovation or in a New Home?

Maybe, so look before you book. The EPA doesn't list renovation or a move as a reason to clean. What it does say is to protect the system during dusty work: "seal off supply and return registers and do not operate the heating and cooling system until after cleaning up the dust."

The industry group Breathing Clean by NADCA goes further. It lists "after home renovations or remodeling" and "prior to occupancy of a new home" among the things that may lead a homeowner to consider more frequent cleaning, along with smokers in the household, pets that shed heavily, and water damage. That is a reason to check for debris, not proof that cleaning is needed. If the registers were left open during drywall work and dust now blows out of them, that fits the EPA's heavy-debris test.

Is Duct Cleaning Worth It for a Rental Property?

The same test applies, whoever lives there. For landlords and property managers, the EPA's three reasons to consider cleaning are the ones to act on: visible mold, a rodent or insect problem, or heavy debris in the ducts. As with any home, deal with the leak or the pests first, or the problem is likely to come back.

The time between tenants is a practical time to check, because the unit is empty and the registers are easy to reach. MedCity Duct Cleaning's commercial duct cleaning service can clean individual units during tenant turnover or a whole building on a coordinated schedule.

How Do You Avoid Paying for a Cleaning You Don't Need?

Ask to see the problem first. The EPA says to ask service providers "to show you the contamination that would justify having your ducts cleaned." Its other advice:

• Compare. "Talk to at least three different service providers and get written estimates before deciding whether to have your ducts cleaned."
• Be wary of health promises. "Do not hire duct cleaners who make sweeping claims about the health benefits of duct cleaning — such claims are unsubstantiated."
• Be wary of schedules. "Do not hire duct cleaners who recommend duct cleaning as a routine part of your heating and cooling system maintenance."
• Don't accept "EPA approved." The EPA "neither establishes duct cleaning standards nor certifies, endorses, or approves duct cleaning companies."

Method matters too. The EPA warns that "an inadequate vacuum collection system can release more dust, dirt and other contaminants than if you had left the ducts alone." If you do go ahead, read what to expect during a professional duct cleaning so you know what a thorough job looks like.

What Can You Do Yourself First?

Quite a bit, and it costs little:

1. Take off a supply register cover and look inside with a flashlight. You are checking for heavy deposits, droppings or anything that looks like mold.
2. Vacuum dusty return grilles, or remove and clean them.
3. Change the furnace filter regularly. The EPA says to "use the highest efficiency air filter recommended by the manufacturer of your heating and cooling system."
4. Have a heating contractor service a fuel-burning furnace before each heating season. The EPA recommends this "to protect against carbon monoxide poisoning." That job belongs to an HVAC technician, not a duct cleaner.

What Does This Mean for Rochester-Area Homes?

The EPA's test is the same in southeast Minnesota, and moisture deserves extra attention here. The Minnesota Department of Health says high humidity "frequently causes mold growth in our climate." It recommends keeping a home's relative humidity "between 20-40 percent in the Winter and less than 60 percent the rest of the year." Controlling moisture comes before any duct cleaning.

When one of the EPA's reasons does apply, MedCity Duct Cleaning's air duct cleaning service covers Rochester, Byron, Kasson, Stewartville, Pine Island and nearby towns. When you request a free quote, we'll assess your ducts and give you an honest recommendation, including when cleaning isn't needed.

Frequently Asked Questions

Is air duct cleaning worth it?

Sometimes. It is worth considering when there is a specific problem: substantial visible mold, rodents or insects in the ducts, or ducts clogged with excessive dust and debris. Without one of those, the EPA says cleaning is probably unnecessary, and it does not recommend cleaning on a routine schedule.

Does the EPA recommend air duct cleaning?

Only as needed. The EPA says it does not recommend that air ducts be cleaned except on an as-needed basis, because of continuing uncertainty about the benefits of duct cleaning under most circumstances.

Does duct cleaning improve health or allergies?

It has not been shown to. The EPA says duct cleaning has never been shown to actually prevent health problems, and that claims of sweeping health benefits are unsubstantiated. If someone at home has unexplained symptoms, the EPA says to discuss the situation with your doctor.

Will duct cleaning lower my energy bills?

Probably not by itself. The EPA says little evidence exists that simply cleaning the duct system will increase your system's efficiency, though some research suggests cleaning dirty cooling coils, fans and heat exchangers can.

Is a dusty vent a sign my ducts need cleaning?

Not usually. The EPA says it is normal for return registers to get dusty, and that the registers can be easily vacuumed or removed and cleaned. A light amount of household dust in your ducts is also normal.

How often should air ducts be cleaned?

There is no set schedule. The EPA says duct cleaning is not considered a necessary part of yearly maintenance, and it warns against hiring cleaners who recommend it as routine maintenance. Clean when you find a reason to, not by the calendar.

Not sure whether your ducts need cleaning? Request a free quote online or call us at (507) 289-4039.

Sources

1. Should You Have the Air Ducts in Your Home Cleaned?, U.S. Environmental Protection Agency
2. A Brief Guide to Mold, Moisture and Your Home, U.S. Environmental Protection Agency
3. Mold and Moisture, Minnesota Department of Health
4. Frequently Asked Questions, Breathing Clean by NADCA