Contact Us

Send Message

Subscribe to our RSS Feed Articles & Tips

Duct Cleaning Keeps Your Home's IAQ High

Many homes can go years without duct cleaning yet the duct system remains problem-free. In other homes, certain conditions lead to a buildup of harmful debris in the ducts within just a few years. Dust, mold, pollen and debris from household pests are all among these. In fact, Chicago's humid summers contribute to conditions that encourage mold growth. 

Professional duct cleaning gets debris out of your ducts so they don't end up in the air you breath. Choosing a skilled duct cleaning professional is essential. A bad cleaning job is worse for your home's air quality than no cleaning at all. A technician trained in duct maintenance brings the knowledge and tools to remove debris without allowing it to enter your living space.

Signs Your Ducts Could Use a Cleaning

Often, dirty ducts give clear signs something is wrong. If your ducts are suffering from any of these symptoms, it's time to schedule a professional inspection.

  • Dust in your home -- Ducts harboring unhealthy amounts of dust may cause dust to build up around your home. You'll notice furniture and other surfaces seem to need dusting more than they should. For another indication, note what happens at your supply registers when your furnace or A/C kicks on. If you see a puff of dust emerge, your ducts are overdue for cleaning.
  • Evidence of mold -- Take a look inside the accessible parts of your sheet metal ducts. If you find splotches of brown, green or other discoloration on the duct walls, it's likely you have mold growing in your ducts. A musty, mildewing odor, moisture and water damage are also warning signs, even if you don't see the mold itself.
  • Pest problems -- Mice, squirrels, cockroaches and wasps are just of few of the creatures that could take up residence in your ductwork. They leave behind droppings, hair, dead insects and damage such as chewed fiberglass or flex duct. Evidence of pests means your ducts should be cleaned or replaced.
  • Unpleasant odors -- In addition to mold and pests, other possible causes of strange smells from the ducts include a pet wetting into the register, air leaks pulling in stale air from the basement or attic, and a long-standing buildup of organic debris.
  • Restricted airflow -- Have one room that never seems to get warm or cool enough or that feels stuffy year round? Place your hand over the supply register in the room to check the airflow. Reduced airflow suggests a possible blockage in the ductwork that duct cleaning will remove.

Not all duct debris makes its presence known. There are times when a home's ductwork is at a higher risk for contamination. At these times, even if you don't notice any warning signs, it's wise to schedule a duct inspection to make sure nothing harmful is lurking in your heating and cooling system.

  • A new home -- A newly built home may have construction-related debris left over in the ductwork. With an older home, it's anyone's guess what could be in there. In either case, an inspection will let you know about any issues and tell you whether or not duct cleaning is in order.
  • Regular maintenance -- Even in the cleanest of homes, ducts can still pick up debris. If your ducts haven't been professionally maintained within the last five years, now's the time. Some duct systems are still perfectly clean after this time, but not all are.
  • Renovations -- Working on your home can leave drywall dust, sawdust, carpet fibers and other material in your air ducts. This is true even if the work wasn't near the ducts themselves. If you've made any major home improvements recently, call in a professional to make sure your ducts are still in good shape.

Your Indoor Air Quality Depends on Clean Ducts

Just through daily activities, a family in the average six-room home can produce up to 40 pounds of dust each year. Even with regular dusting and vacuuming, some of that is bound to end up in the ducts where it gets recirculated in the air.

On top of that, if mold develops in your ducts, it will send out spores that also circulate through the air. These spores can trigger asthma attacks and allergy symptoms, as well as spread mold around your house. Pest droppings, dead insects and dead rodents in your ducts also give off contaminant particles that can worsen or cause respiratory conditions.

Exposure to airborne biological debris, such as cockroach droppings and mold, can increase even a healthy person's risk of respiratory tract infections, warn experts from the American Lung Association. Keeping your ducts debris-free is one way to ensure your home's air stays as clean as possible.

Fresher, healthier air isn't the only benefit of cleaner ducts. Depending on the degree of buildup in your ducts, a good cleaning may also improve your heating and cooling system's efficiency. If the buildup or blockages are severe enough to restrict airflow, they force your blower motor to work harder, causing it to use more energy and preventing certain rooms from reaching comfortable temperatures. Duct cleaning improves your comfort and may lower your energy bills, too.

How Duct Cleaning Happens

An inexpert attempt at duct cleaning will only knock debris loose and allow it to be blown into your living space. A professional uses specially designed tools that efficiently remove debris so it isn't released inside your home. The process works something like this:

Inspection -- Your technician will inspect your ductwork and other parts of your heating and cooling system for signs of dirt buildup, mold, pests infestations, and other problems. Cleaning isn't always the best solution to dirty or damaged ducts. If another option, such as replacing the ducts, is preferable, the technician will let you know.

Set-up -- A filter or cover will be placed over your supply registers and return grills to prevent contaminants from escaping during the cleaning. The technicians may also cover some of your furniture to protect it from the movement of workers and equipment.

Component cleaning -- A HEPA-filtered vacuum will be used to clean parts of your system other than the ducts. These components must be cleaned to so they don't recontaminate the ducts. Components to be cleaned include:

  • Blower fan assembly
  • Fan motor housing
  • A/C evaporator coil
  • A/C drip pan
  • Register and grille covers

Creating negative air pressure -- A negative-air machine, something similar to a giant vacuum, will be hooked up to the main trunk line of your duct system. This equipment may be a truck-mounted machine or a portable machine that's brought inside your home. It creates a strong suction to pull out debris as it's loosened, so the debris never enters your home's air.

Removing debris -- While the negative-air machine is running, your technician will use specialized tools to remove debris from inside your ducts. Tools that may be used include an air whip, rotating brush and compressed air. The technician will use gentler tools on fiberglass ducts, which are more fragile than sheet metal ducts.

Final inspection -- Once the duct cleaning is done, the technician will perform a final inspection. Some technicians also supply before-and-after images of your ducts so you're assured the ducts have been sufficiently cleaned.

If mold was found in your ductwork, the technician may suggest applying a biocide to kill the mold and prevent its regrowth. The most common choice, Sporicidin, is rated by the Environmental Protection Agency (EPA) as "low/very low" toxicity. Some biocides can cause eye, nose and throat irritation, however, so discuss the possible effects with your technician before you allow the use of biocides.

Find a Skilled Duct Cleaner

Following a few simple guidelines will help you find a heating and cooling contractor with the training and tools to perform an impeccable duct cleaning job.

  • Referrals -- Ask neighbors, friends, and family to recommend contractors they've worked with successfully. Collect names of at least three companies.
  • The basics -- Beyond checking for licensing and insurance, also make sure the technician who'll be working on your ducts has a few years of experience, preferably on homes similar to yours. Choose a pro who's willing to do a thorough inspection and suggest alternatives to duct cleaning if appropriate.
  • NADCA certification -- Check that the company is a member of the National Air Duct Cleaners Association (NADCA) in good standing. NADCA offers training, examinations, and certification in matters related to duct maintenance. To become a member, a company must have at least one technician certified to perform duct cleaning.
  • References -- Request contact information for two or three past clients and follow up to see if customers were satisfied with the company's service.
  • Written estimates -- A contractor should be willing to provide an estimate in writing, not just over the phone.

To find a skilled, reliable duct cleaning expert, visit us online at Our Find a Contractor service makes it easy to get in touch with a trustworthy professional in Chicago, Northwest Indiana or Southwest Michigan.

Back to Articles