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What Is Negative Air Pressure? How Can It Be Corrected?

commercial-hvac-fans-in-rotationWhen you think about indoor air quality problems for your commercial facility, your mind probably goes directly to contaminants circulating through the ventilation system or various indoor pollutants. But one of the biggest issues for commercial indoor air quality is negative air pressure

The simple definition of negative air pressure is that it’s when the air pressure inside the building is lower than the pressure outside the building. This often happens in commercial and industrial facilities because of over insulation designed to improve energy efficiency. If not enough outdoor air can enter because of the strong heat-sealing, the indoor pressure will be lower than the outside. Negative air pressure can also happen because of poorly constructed or damaged ventilation systems or malfunctioning equipment that draws on too much air inside the space. 

This might sound benign, but negative air pressure for a commercial facility creates several major problems:

  • It leads to stale, unhealthy air and encourages the growth of mold and mildew. 
  • It allows chemicals, odors, and other industrial/commercial byproducts to linger in the air for longer.
  • It raises the danger of carbon monoxide and radon inside a facility. 
  • It makes it more difficult for gas-fired equipment to operate effectively and efficiently.

When you add all these together, you can see that negative air pressure means a less healthy work environment, lower energy efficiency, and an increase in maintenance and repair needs. 

Solutions to Negative Air Pressure

There are several ways commercial indoor air quality specialists can correct troubles with negative air pressure inside a building. For example, energy and heat recovery ventilators allow a commercial space to circulate fresh air through the building without losing energy: the units pre-heat or pre-cool the incoming air (depending on the outdoor weather) using the energy already inside the building. 

One of the most effective tools we use for negative air pressure is the make-up air unit (MUA). These devices pull in outdoor air to create a slight positive air pressure inside the building. In other words, they “make up” for the air lost inside the building to processes and equipment. 

Make-up air units are designed to ensure the indoor air pressure doesn’t end up becoming too positive. Slightly positive air pressure helps to create a balance because it pushes against the outside air. Too much positive pressure, however, and the building will start to waste energy as excess air flows out. 

Do You Have Negative Air Pressure in Your Facility?

If you suspect your commercial facility has negative air pressure, call our specialist for an analysis of your indoor air quality in Richmond Hill, ON. We can determine if your facility has negative air pressure and why. Then we can find the best solutions. We not only install devices like make-up air units and other ventilation systems, we repair and maintain them as well. We’re experts when it comes to air balancing and proper ventilation for commercial and industrial buildings. 

Advantage Airtech Commercial Ltd. is the Double “A” Name with the Triple “A” Rating! Call us for commercial and industrial HVAC service in the Greater Toronto Area.

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