by Ali Kriscenski

Your building’s HVAC system plays a central role in occupant health, well-being, and productivity. Regular preventative maintenance and repairs can help improve system efficiency, indoor air quality (IAQ) and energy efficiency. Air duct maintenance and cleaning are important aspects of HVAC system efficiency with benefits to your operational bottom line.

Importance of Air Duct Integrity

Your facility’s HVAC system can be compromised by damage, wear and tear, and pollutants. When these issues occur in the ductwork, they can create inefficiencies in air distribution that result in overworked equipment and occupant discomfort. System defaults, higher energy bills and occupant health conditions can all be caused by dirty or damaged ductwork.

Damaged ductwork can occur during general renovations or repairs. This condition can restrict air flow causing an imbalance of airflow throughout a facility. Without proper balancing, equipment will work at higher capacity to reach minimum setting requirements. In short, you will incur higher energy costs with lower energy efficiency and lower thermal comfort satisfaction. Damaged ductwork will also shorten the lifespan of your HVAC components and devices that work to meet higher demand than initial system design requirements.

Dirty ductwork can have similar issues, and often be exacerbated by damaged areas that create collection spots for dust and other pollutants. As forced air moves throughout a building the air currents can pick up particles from within ductwork and deliver them into occupied spaces. When ductwork and filters are dirty, a building’s HVAC system can become a source of allergens and contaminants that cause health issues for occupants. 



The Role of IAQ in Building Performance

As a building owner or manager, you’re responsible for the health, safety, and wellbeing of the occupants. Your building’s HVAC system is central to maintaining optimal conditions for human occupancy. IAQ relates to many factors including air temperature, humidity levels and the levels of pollutants in and around a building. These can include cigarette smoke, volatile organic compounds (VOCs), exhaust, radon, pesticides or cleaning supplies. Providing an indoor climate free of pollutants depends on the efficiency and condition of plumbing, electrical and HVAC systems.

Many building codes and standards today work to address the effects of sick building syndrome (SBS), which increased in parallel with changes to building envelope permeability. SBS is seen in buildings with pollutants, allergens and contaminants, and improper ventilation. Air conditioners, humidifiers, and occupant activity all contribute to the aerosolization of toxins, molds, and microbes of biological contaminants. These airborne particles can cause health issues such as eye and throat irritation, asthma, fatigue, nausea, and headaches. If the building occupants are also your workforce, IAQ  plays an even more significant role in your business operations, affecting absenteeism rates and productivity.   

Maximizing HVAC Efficiency with System Maintenance

As HVAC systems play a significant role in building performance and occupant satisfaction, regular maintenance is critical to IAQ, energy efficiency, and operational costs. Your maintenance schedule should factor in seasonal changes that could affect temperature and humidity, should adapt to consider renovations or other building changes, and also any external factors that could affect system performance, such as extreme weather or natural events like forest fires. 

How Often Should You Clean Your Air Ducts?

As part of regular HVAC maintenance, your HVAC experts at Therma can establish routine air duct cleaning at least every 3-5 years. In facilities with higher levels of airborne particles, such as hospitals or manufacturing facilities it may be beneficial to perform cleaning more often. In addition to regularly scheduled cleaning, there are instances when ductwork cleaning or replacement should be prioritized, including:

  • Water damage in ducts
  • Microbial growth in ducts
  • Debris in ducts impacting air flow
  • Dust discharge from supply diffusers
  • Offensive odors from ductwork


Work With HCAV Specialists

In commercial facilities, in-house facilities teams can work together with HVAC specialists to set system performance baselines, create a maintenance and cleaning schedule, and design a plan for long-term system upgrades. With preventative measures and regular cleaning, you can maximize the efficiency, effectiveness, and lifespan of your HVAC system. Contact Therma today to get started.


​​Ali Kriscenski was trained in high-performance building design at Boston Architectural College. She has worked with leading architecture and construction firms in NYC and New England and served on the executive team at the Forest Stewardship Council International. She was the managing editor at Inhabitat and has worked pro bono for the Green Building Institute, ISEAL Alliance and Habitat for Humanity.



WebMD – Sick Building Syndrome

United States Environmental Protection Agency (EPA) – Introduction to Indoor Air Quality 

American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) – Thermal Environmental Conditions for Human Occupancy