What Is Antimicrobial Sealant & What Is It Used for

What Is Antimicrobial Sealant?

Antimicrobial sealant is a coating that a duct service technician places on ductwork to prevent bacterial growth or future recontamination. Several duct sealant brands feature different chemical compounds, benefits, and safety information. Always ask your intended air duct cleaning company what antimicrobial sealant they intend to use, and do your research before agreeing to its usage. While many solutions are effective at protecting your ducts, some may require that home residents leave the premises during application.

Like any other at-home service, having your ducts coated with antimicrobial sealant should be a choice, and no company should pressure the application without a reason to do so. Standard duct cleaning usually consists of the physical removal of debris from your air duct with professional-grade vacuum equipment and brushes. Many duct cleaners will include antimicrobial sealant as an additional add-on to a regular duct cleaning service. In this case, sealant application is not required but suggested for ducts with previous infestation or mold growth problems.

What Is Antimicrobial Sealant Used For?

Antimicrobial sealant on air ducts can remove in-duct bacterial contamination and protect them from future contamination. As described by the National Air Duct Cleaners Association’s guidance on HVAC chemical applications:

Numerous types of contamination may be found within HVAC systems. Depending on the environment and conditions, these contaminants may contribute to mold/ mildew (i.e., fungal growth) and other microbiological growth. Other contaminants may include debris from outside air sources, fire damage residue, dust, vermin, etc.

When done safely and under the right conditions, antimicrobial sealant application may remove residual contaminants that are invisible to the naked eye, such as mold spores. As the solution dries on the duct, the barrier it leaves behind may also continue killing bacteria in the duct after initial application, helping prevent regrowth.

Here are a few situations when your HVAC cleaning company may suggest you apply antimicrobial sealant:

  • Mold or mildew growth
  • Vermin nesting or insect infestation
  • Large smoke-residue buildup on duct surface
  • Significant construction debris dust buildup within the duct

What Is Antimicrobial Ductwork?

In contrast to antimicrobial sealants that apply topically, antimicrobial ductwork’s sealant is built-in to prevent contamination. In this case, the air duct's material is bacterial resistant and features an antimicrobial coating.

There are some pros and cons to antimicrobial ductwork. A positive aspect is that the installation is safe and does not use formaldehyde. The ductwork also helps protect your entire HVAC system from mold growth, vermin infestation, and other common air duct contaminants.

On the other hand, this ductwork is often considerably more expensive up front than other air duct alternatives. The additional material costs and advantages increase initial investment, with some antimicrobial ductwork installation prices being higher than many other duct services.

Though it offers more upfront protection, many homeowners may also not want to replace their entire duct system, especially if their in-duct contamination issues only happen occasionally.

How long does antimicrobial air duct coating last in my HVAC system?

How long any antimicrobial air duct coating lasts depends on the sealant used and its application. Many sealant coatings will last at least a few years if applied properly.

To know how long your antimicrobial coating for ductwork will last, ask your service provider. They should be able to give you the expected coating life from the sealant manufacturer or at the very least point you in the direction of that information. Like all other parts of air duct service, do your own research on the products your duct technician uses before allowing the application to your duct system.

Benefits of Air Duct Cleaning Services:

Though antimicrobial sealant may aid in certain duct contamination cases, everyday air duct cleaning services still offer several benefits to homeowners. Note that air duct cleaning should be scheduled in specific circumstances, including:

  • Duct Blockage or Clogging
  • Mold Growth
  • Vermin Infestation
  • After In-Home Construction or Remodeling

When done by a professional and for the right reasons, air duct cleaning has many potential perks and can improve your home safety and indoor air quality. Below are some of the most common benefits of air duct cleaning.

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Cleaner, Healthier, and Safer Air

If there is something present in your duct system that negatively impacts your air quality (such as mold spores, debris, or smoke residue), an air duct cleaning should remove the contaminants and improve your air. This is especially important if you experience symptoms related to dirty air ducts or your health is affected. In these cases, professional cleaning may remove the cause of those symptoms, improving your indoor living experience.

Bad Odor Removal

Odor removal is another potential benefit of an air duct cleaning service, especially if your ducts house infestation. Mold growth and vermin nesting can cause unpleasant odors to circulate through your ducts and into your home. If you notice a similar musty or foul smell traveling from room to room, you might want to consider a professional duct inspection and cleaning.

Mold Removal

As previously mentioned, air duct cleaning can help remove the mold growth and help protect your ducts from regrowth. In a cleaning, your air duct technician will use powerful vacuums and brush tools to remove the low-level mold growth and mold spores from your ducts. Once cleaning is complete, you can worry less about breathing in harmful fungus or bacteria.

To get the best results from air duct cleaning, make sure that you choose a trusted, reliable, and professional air duct cleaning company. While it may be tempting, you should never attempt to clean your air ducts yourself. Doing so can negatively impact your air quality and will often not give you the same benefits as professional cleaning.

To learn more about air duct cleaning benefits and how to find a trustworthy air duct cleaning company, take a look at our previous article on air duct cleaning benefits. It will provide you with more in-depth information on this service and give you tips to aid you during your business search.

Benefits of Having an Antimicrobial Air Duct Sealant:

Antimicrobial air duct sealants can increase the benefits of traditional air duct cleaning by adding extra sanitizing power and lasting protection to your air ducts. With this in mind, here are some of the benefits of antimicrobial air duct sealant application:

Increased Duct Sanitization

The primary benefit of antimicrobial sealants is widespread duct sanitization. Antimicrobial sprays and sealants may be more effective at removing unwanted or dangerous duct bacteria than vacuuming or dry brushing alone. Much like sanitizing any other part of your home, applying a duct antimicrobial can give your system a deeper clean and eliminate contaminants.

Increased Duct Protection

Increased duct protection is another potential benefit of antimicrobial sealant application. After being applied, the sealant can create a barrier between the duct surface and the air, dust, and bacteria around it. After mold growth or infestation, antimicrobial applications can help protect your duct against future recontamination.

As with any chemical-based application, air duct sealant may increase home exposure to certain compounds. As the NADCA states, “overuse of antimicrobial products can lead to needless exposure to chemicals.” For this reason, you’ll want to consider how you feel about an in-home chemical application and the benefits of the sealant when scheduling the service.

To get the most out of your sealant application, ensure that your air duct company is well-trained in sealant application and takes the necessary safety precautions, such as asking home residents to leave the residence during the sealing process.

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Which Is Better, an Air Duct Cleaning Service or Antimicrobial Air Ducts?

Whether air duct cleaning or antimicrobial air ductwork is better depends solely on your needs, budget, and duct history. Looking at some comparisons may help you when deciding which route to go with for your duct system.


With antimicrobial ductwork, you will pay the cost of the air ducts, plus a system installation cost. These air ducts may have a greater price upfront but could protect your system from mold remediation costs in the future.

Air duct cleaning cost depends on the business cleaning prices and technician availability. Typically, the price will be much lower than antimicrobial air ducts, but you may have to schedule a cleaning more often.


Antimicrobial air ducts may be more effective than standard duct cleaning in terms of lasting bacterial protection. The sealant on antimicrobial air ducts improves your system’s resistance to bacteria and harmful particles.

On the other hand, air duct cleaning can remove large amounts of dust, debris, or buildup from your system - something antimicrobial air ducts do little to remedy. Duct clogging can still occur in antimicrobial air ducts. Even if you invest in these ducts up front, you may still need to schedule an air duct cleaning service if you have an air duct blockage.

It makes sense to buy antimicrobial air ducts if you have consistent mold issues or concerns about in-duct bacteria. However, for the average homeowner, air duct cleaning is enough to remove major system concerns at a lower price.

Are you currently searching for a reliable air duct cleaning service? If so, Filterbuy Local can help. You can rely on our trained technicians to clean your ducts and improve indoor air quality. Our customer service representatives are available and would be happy to answer any questions you may have.

Click here for more information on Filterbuy Local Air Duct Cleaning services.