When Should You Consider Replacing Your Ductwork

October 20, 2021
Ductwork Replacement in Seattle, WA

HVAC ductwork is quite likely the last thing that comes to your mind as you go about your usual activities within the house. Air ducts are normally hidden; however, they still require attention, maintenance and repair from time to time.

Air ducts are fundamental components of your HVAC system because they circulate conditioned air throughout your residence. Because of their importance, it is prudent to be on the lookout for any signs of faulty operation and seek professional repair and maintenance services from experts at a company such as Brennan Heating & Air Conditioning if you notice any. We provide duct cleaning and installation services throughout western Washington State.

The Importance of Air Ducts

When scheduling HVAC system maintenance, it is paramount to have the ducts factored into the process. They are essential in collecting used air from different rooms of the house, directing it to be cleaned, heated or cooled and later circulating it back throughout the house.

Neglecting the ducts ultimately leads to a loss of your HVAC system’s efficiency, causing increased energy bills. For instance, if holes are present in the ductwork walls, they can lead to a significant reduction in proper airflow. By allowing conditioned air to escape into the walls, holes also lead to insufficient heating and cooling.

Air ducts can last for many years, but they need regular cleaning and inspection to work as efficiently as possible. If any of the following applies to your ductwork, it’s time to call on an HVAC technician for a thorough inspection. If you’re located in or near Seattle, one of our experts at Brennan Heating & Air Conditioning would be glad to assist you in this.

Indicators That You Need to Replace the Ducts in Your Home

As we’ve already said, your ductwork can hold up for a long time, but nothing lasts forever. The following discussion covers some of the symptoms, considerations and warning signs that might alert you to the need for ductwork replacement.


With proper care, air ducts can easily last 10 years or more. However, due to environmental factors, they are susceptible to wear and tear, and you may find that they do not hold up as long as you’d planned for them to.

Most of us will assume that as long as the ducts are functional, they are all right, but it isn’t always the case. This is especially true of very old ducts that were installed when dangerous materials such as asbestos were used for insulation purposes. If that’s the case in your home, replacing the ducts will not only improve your HVAC system’s functioning, but it will also help protect your family’s health.

Noisy Operation

When operating, your HVAC system will likely produce low-level noise as it circulates conditioned air throughout the house. Occasionally, your ducts will make a quiet popping or crackling sound, but this will typically stop once the ducts heat up. If loud rattling sounds start coming from the ducts, it indicates that there is a problem, and you should seek inspection services to identify the faulty or loose duct section.

Often, you will hear the rattling sounds when ducts become loose at either the joints or the hinge sections. You may also hear a whistling or howling sound from your ducts. This is a sign that there are holes allowing air to escape from the ductwork.

Spike in Energy Bills

It is common for a small amount of air to escape from the ducts during the circulation cycle. In fact, it’s estimated that up to 20% of conditioned air can be lost. However, losing more than 20% of your conditioned air indicates that your ductwork needs to be replaced.

Increased air loss beyond this margin will lead to decreased system efficiency. The HVAC system is forced to work harder to make up for the lack, consuming more energy in the process. Having an HVAC professional inspect your ducts for inefficiency can help determine if it’s time for a replacement.

Uneven Heating or Cooling

Uneven heating or cooling in different areas of your home can be caused by air escaping through openings and leaks within the duct system. You can confirm uneven heating or cooling by using a thermometer to check the temperature in different rooms. You might also notice uneven airflow throughout your home.

If you have uneven heating, cooling and/or airflow, first check to make sure that vents are not blocked or closed in particular rooms. Once you’ve ruled out the vents as the cause, it’s time to turn to the ductwork. In addition to leaks, clogs in the ducts could also be the culprit of your uneven temperatures and airflow.

Presence of Dust Accumulation in the House

An accumulation of dust within your house indicates that your duct system is faulty and not operating to its full potential. When they’ve been neglected, your ducts can experience a buildup of dust and other debris. Once the HVAC system kicks on, this debris will be sent throughout your living spaces, leading to excessive dust on furniture and other surfaces. Dust and debris can also exacerbate allergy symptoms and lead to other health issues.

Smells of Mold and Mildew in Your House

Uneven temperatures that are caused by air leaks in the ductwork can facilitate mold growth. For example, as warm air flows through the cold ducts, condensation can occur. This water provides a thriving environment for mold and mildew to grow. Eventually, you will start to smell the mold as the HVAC system operates.

In addition to creating an unpleasant smell, mold in the ductwork poses a risk to your health. Mold spores can also be circulated to other areas of the house, increasing health risks and potentially damaging materials in your residence. If you detect such smells, it’s best to reach out to get expert services in duct repair and replacement as soon as possible.

Pest Infestation

The presence of holes within your duct system causes air loss problems and exposes your ducts to potential pest infestation. Pests find entry points through the holes or leaking sections and create colonies within the ducts, leading to an array of problems. Some issues associated with a pest infiltration in your ductwork include the following:

  • Unpleasant smells
  • Noises in the night
  • Spread of bacteria
  • Very poor air quality

In addition, if small bugs make their way into the HVAC unit, they can cause electrical faults and render the unit nonoperational. A major pest infestation can also completely block your ducts and create structural damage within the ductwork.

Experiencing Respiratory Issues While in Your Home

Often, respiratory health problems within the home are associated with inhaling dust particles and other debris. Faulty and open ducts facilitate the entry of allergens like pollen and dander and circulate them throughout the household. Pollen grains are known to cause asthmatic problems. To avoid such issues, it’s advisable to schedule regular inspections and cleaning from ductwork experts.

Improper Installation

Ductwork systems are strategically designed to heat and cool different areas of your home while supporting HVAC efficiency. Ducts that are improperly designed or installed can lead to significant energy loss within your residence. If you identify uneven heating or cooling, it may be attributable to poor design or installation.

Air duct repair and replacement require the expertise of professionals such as those from Brennan Heating & Air Conditioning. We provide a full range of HVAC services, including heating and cooling maintenance, repair and installation. Our team also provides energy consultations, electrical services and water heater repair in Seattle and the surrounding areas. Contact Brennan Heating & Air Conditioning today for more information or to schedule an appointment.

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