Ventilation Systems

Building Ventilation Systems: How Much Ventilation Do I Need?

building ventilation systemBuilding Ventilation Systems

Ventilation is the process of bringing fresh outdoor air into a building to replace contaminated indoor air. Mechanical ventilation distributes airflow to rooms within a facility by way of fans and ductwork.

Returning to your building after COVID-19 lockdowns generally does not require a new building ventilation system. Many building owners and facility managers, however, are increasingly implementing building ventilation system upgrades and improvements to deliver more clean air to occupants.

The amount of ventilation your building needs to improve IAQ largely depends on several factors, including your facility, how you use it, and how your HVAC systems are running. Ventilation techniques have significantly improved over the last few decades and is now believed to have a direct impact on building occupants’ health and productivity. 

In addition to opening windows and using fans, facility managers and building owners can improve ventilation by increasing total HVAC airflow to occupied spaces, increasing air filtration, properly maintaining air filters, and implementing ultraviolet germicidal irradiation.

Increasing the amount of outdoor air coming into your building can help control temperature, humidity, pollutant levels, odors, and other factors that can impact your occupants’ the health. Air exchange rate is the rate at which indoor air is replaced by outdoor air. This number can largely differ depending on building applications and may vary by state codes.  

For more information of state indoor air quality regulations and policies, check out our interactive IAQ Map.

How Can I Determine the Ventilation Rate of my Facility?

When determining the ventilation rate of your building, there are five factors that can come into consideration: ventilation system design, outside air supply, outdoor air quality, equipment maintenance, and controlling other pollutant pathways.  

As all buildings are designed differently and serve different uses, determining the ventilation rate of your building depends on things such as the number of people in your building, the amount of equipment you have, and the purpose of use. For instance, if you use an area within your building differently than its original purpose (such as converting a closet into meeting space), your HVAC system may require modifications to accommodate such changes.   

Outside air that is delivered through your HVAC system helps dilute the many pollutants let off by building materials, equipment, people, furnishings, and more. Your outside air supply is critical in providing comfort in occupied spaces. Outdoor air pollutants, like carbon monoxide, can adversely impact your indoor conditions when it enters your building’s ventilation system, which is why choosing the right air filter and properly maintaining it is important. Additionally, you may have to take the placement of furniture and equipment into consideration – equipment that generates heat (such as computers or monitors) can impact the delivery of air to occupied spaces and cause your HVAC system to deliver air that is too cold.  

By diligently maintaining your HVAC equipment, you can contribute to adequate air delivery and quality. When it comes to addressing other areas of your building where pollutants can spread, such as elevator shafts and stairwells, you may need to provide special ventilation control measures to manage such sources.  

Have another question about Indoor Air Quality? Contact us today at 866-470-0827 or email your question to!