A home’s heating, ventilation, and air conditioning (HVAC) system is an important element in any home. Like any other major part of the home, maintenance and care are important aspects for the health and comfort of those living inside. It’s also good for the health of the family budget over time.

The National Air Duct Cleaners Association (NADCA) says the average 6-room house collects 40 pounds of dust and allergens in their air ducts every year. Dust accumulation in ducts can provide an excellent home for dust mites, bacteria, fungi, and mold, all of which present allergen and respiratory hazards. The Environmental Protection Agency (EPA) reports that poor indoor air quality is one of the top five health risks for people in the United States today. Additionally, the American Lung Association says that people spend up to 90% of their time indoors. The elderly and those suffering from respiratory illnesses benefit enormously from regular cleaning of air and ventilation ducts.

For homes with central heat and air, every time the system turns on, those built up contaminants get forced back into the rooms where families spend their time living and sleeping. Children in particular are vulnerable to the bad effects of these pollutants. Their respiratory rate is faster than that of adults and they inhale more air to body mass. For very small children, they are closer to the floors (if not playing right on them) where dust borne pollutants build up.

If the potential health concerns aren’t enough to convince anyone about the importance for regular cleaning of their ventilation ducts, remember that the efficiency of the system becomes compromised as more and more debris builds up. This translates to monthly heating and cooling bills also increasing. The EPA says that just a millimeter of dirt built up on a heating or cooling coil can reduce efficiency by 21%. Repairs for heating and cooling failures are often caused by dirt build up, as many as 90%, according to the Louisiana Cooperative Extension Service. These kinds of repairs are not only inconvenient but are often expensive.

So how often should a homeowner have their HVAC system cleaned? Every three to five years is the typical recommendation. A lot of other factors need to be considered before deciding how often to have your ducts cleaned. Smoking in the house or indoor pets that produce dander and shed hair means build up in the ventilation system will happen faster. Residents who have respiratory problems or are at risk of respiratory problems should clean their duct system more often.

It is recommended to hire a professional cleaner when there has been a pest infestation that affects the ducts, like rodents or insects. It is also a good idea to have professionals come out to your home and clean if there is visible mold present anywhere inside any part of the system.