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The Details in the Dusting: Sweeping Up the Facts on Air Duct Cleaning

Written by  Sam Burroughs


A building’s HVAC system supplies and removes air naturally through windows or through mechanical means, according to the National Institute for Occupational Safety and Health (NIOSH), and is made of many mechanicals components. These systems ensure that the air that is provided is clean, of a comfortable temperature and at a comfortable humidity level.

The operations and maintenance of these systems sit at the heart of keeping a building’s ventilation system operating at its best.

According to NIOSH, improper upkeep and use of HVAC systems is one of the most common problems for workplace indoor environmental quality. Through ventilation, proper movement through the ductwork and filtering, the occasional cleaning of these systems can be essential for your clients.

You can offer basic air duct cleaning on an as-needed basis. As the allergy season gets under way, your clients will know they have a company that is not only looking out for their building’s long-term health, but for them as well.

A building’s ventilation system is used to remove common pollutants such as: carbon dioxide, carbon monoxide, tobacco smoke, mold, bacteria, fumes from cleaning products, pesticides, vehicle exhaust and fumes from copy machines and printers.

Maintaining the HVAC system requires constant attention. One of the ways you can aid in this is through occasional, thorough and proper air duct cleaning.

Why Air Duct Cleaning?

The Environmental Protection Agency recommends having air ducts cleaned if there is visible mold growth on the surface of the ducts, the ducts are invested with vermin or the ducts are clogged with excessive amounts of dust, dirt and debris that are released from the registers.

It is important to note that the presence of dust alone does not indicate a dirty air duct. According to the EPA, there are no studies that conclude that dust levels increase because of dirty air ducts. However, if any of the above conditions are present there may be underlying causes in the building that you should address.

Air duct cleaning can also be a service you offer to not just address and fix a problem, but to prevent one.

Occasional cleaning of the air ducts is a good way to maintain the integrity of the building’s entire ventilation system. Not only can occasional cleaning be a good way to become notified if there is an underlying problem occurring, some studies have shown that cleaning HVAC components when needed may improve the system’s overall efficiency.

Air ducts should not be cleaned regularly and must be done properly every time. This is a service you should offer your clients as-needed.

Why Occasionally?

The indoor air quality (IAQ) of buildings is often used as a way to cash in on people’s fears about breathing in invisible containments. This can be especially prevalent during the spring cleaning season when a lot of clients are trying to minimize the onslaught of outdoor allergens from affecting their IAQ.

Scaring clients into paying for frequent air duct cleaning could do more harm to the lifespan of the HVAC system than good.  However, being well-informed on this topic means that you can help your client achieve peace of mind through occasional, reliable duct cleanings.

Biocides? Sealants?

When offering this service, it is important to understand the cleaning products that could be used and their pros and cons.

The use of biocides to kill bacteria, fungi and prevent future mold growth and sealants to prevent dust particles from being released into the air or seal air leaks are only appropriate under certain circumstances, according to the EPA. The available research on these chemicals has not demonstrated their effectiveness or their potential health side effects.

During the spring cleaning season, you may find that a lot of products are being used to remove dust, clean out closed-off spaces and refresh areas. Minimizing the amount of chemicals you use will not only lower the cost to you, but will also marginally eliminate the possibility of potentially causing unwanted health problems.

There are currently no chemical biocides that are registered by the EPA for use on an internally-insulated air duct system, according to their website. Being transparent about the pros and cons of these products can also help your clients feel confident in their decisions when it comes to paying for an additional service you offer.

What's the Cost?

Companies will charge between $450 to over $1,000 for air duct cleaning services. What you should charge is based on your qualifications as a provider, which components of the HVAC system you will be offering to clean and the type of cleaning you’ll be doing.

Offering duct cleaning can refer to a laundry list of parts that include: supply and return air ducts and registers, grilles and diffusers, heat exchangers, heating and cooling coils, drip pans, fan motors and fan housing.

Your cost will also depend on what you decide is the best method of cleaning. Applying biocides and sealants will cost more than just vacuuming out the vents. 

Other price qualifications include: the size of the system, system accessibility, level of contamination and the climatic region.


Ideally, being a certified HVAC contractor is the best route for investing in duct work services. However, other certifications may make it possible for you to add on this service to your existing business structure.

Another option is to obtain certification from the National Air Duct Cleaners Association (NADCA).

The NADCA offers information on how to become certified as an air systems cleaning specialist (ASCS) and a certified ventilation inspector (CVI).

The ASCS and CVI certifications will increase how much your service is worth and increase your overall market value. To become certified through the NADCA, you must review the ASCS candidates guide, study the material either in class or independently and then register for the ASCS certification exam.

To find out more, you can visit nadca.com to find out if these certifications are right for you.

The NADCA will direct people who content them about duct cleaning to certified cleaners, expanding your credibility in the market.

An air duct cleaning license is required in several states. It is important to check out state and local government resources to get the proper information regarding your state’s standards for                                         duct cleaners.

How is it Done?

If duct cleaning is done improperly, you risk increasing the amount of dirt and dust particles in the air, effectively lowering its quality.

Here is a brief rundown of what duct-cleaning is going to look like: First, open access ports and doors to inspect the system. You will need to make sure there are no asbestos - containing materials, according to the EPA. These require special procedures and should be done by specially trained contractors.

Next, you will either need to use vacuuming equipment that exhausts particles outside of the building or HEPA vacuuming equipment.

Make sure all furniture and floors are properly protected. Then, through brushing of the duct surfaces and vacuum cleaning, you will able to dislodge dust, dirt and debris. Fiberglass duct board and sheet metal ducts lined with fiberglass require soft-bristled brushes only.

Then, you will seal and re-insulate access holes.

For additional information on what duct cleaning will entail you can visit the NADCA’s website at nadca.com for more market standards. You may also look at the North American Insulation Manufacturers Association at naima.org for recommended practices on cleaning ducts with fiberglass.

In conclusion

As long as periodic duct cleaning is done properly, this is a service that could put your client’s worries at ease during this time of year as the heating is shut off and buildings start turning to air conditioning. 

It is important to understand the research surrounding duct cleaning so you can provide a top-quality service to your clients that prevents costly damage to their HVAC system.

Air duct cleaning is a complicated and well-finessed niche in commercial cleaning. It takes a lot of proper education, training, experience, equipment and judgment to properly perform this service. Researching this topic is your first step in evaluating if you should take on this added service to diversify your business.

For more information, visit: epa.gov/indoor-air-quality-iaq/should-you-have-air-ducts-your-home-cleaned.



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