Geary Pacific Supply

Geary Pacific Supply

Methods of Ventilation

Posted on Monday Aug 16, 2021 at 08:13AM in IAQ


What method of ventilation will work best for me?


Recently, studies have shown that increasing or adding ventilation to an occupied space can reduce the potential transmission of COVID-19. There are many methods to bring fresh air into a building, but which way is the best? Each have their pros and cons!


There are 3 main method types of ventilation. Exhaust (negative), supply (positive), and balanced.


1. Exhaust or Negative Pressure Ventilation

This type is most commonly found in a residential application where they utilize the bathroom and laundry fans to push air out of the home, while pulling air in. This is the cheapest method but has its flaws. In order to have air from within the home to push out, there needs to be outside air coming in. With exhaust ventilation, it puts the home into a negative pressure and pulls outside air into the home from anywhere possible. This is potentially problematic due to not having control where the air comes from and the inability to control the quality or temperature of air that is coming into the building, increasing energy costs.


2. Supply or Positive Pressure Ventilation

This will work in both commercial and residential applications by using manual outside air dampers, economizers, or ventilators attached to the HVAC equipment. There is a varying level of control with this type of ventilation system using electronic or manual controls. With the ventilators attached to the HVAC system, there is the ability to filter the incoming air to remove particulates while also controlling the location of where the outside air is being pulled from. Outside air is being pulled into the building and mixing with the circulating air inside the HVAC system and pushed into the space through the air ducts, creating a positive pressure and then finding its way out of the building though leaks in the windows, doors, or walls.


3. Balanced Ventilation

Balanced Ventilation is found in both commercial and residential applications typically using a Heat or Energy Recovery Ventilator. This type of system can be attached to the existing HVAC system or used all on its own. While this can be an expensive option, it will reduce the extra amount of heating or cooling costs that are added as outside air is brought in. HRV or ERVs pull air into the building, while at the same time, pushing inside air out. These systems will also filter the outside air and use the conditioned air to pre-heat or pre-cool the outside air coming in utilizing a heat exchanging core. Using this type of system gives you the best control of the air temperature, quality, and quantity. Because this can be used separate from the HVAC system, it can be used with mini splits or VRF (variable refrigerant flow) ductless systems in order to satisfy ventilation requirements.


Figuring out which of these ventilation methods is right for you can be a hassle, let Geary Pacific’s team of specialists help you solve your ventilation needs.



No one has commented yet.
Comments are closed for this entry.