Prevent Sick Buildings: Why Positive Building Pressure Matters

Can a building get sick? I’ll give you the answer up front: Yes, sure, most definitely — a building can get “sick.” You may ponder… “But how can a building become sick? It is an inanimate object. It doesn’t live and breathe like humans!” On the contrary, your building is a living object. The main factor making your building come alive is its people: your customers, employees, and outside partners (think mail delivery or an overnight cleaning crew). Let’s dive into what factors can make a building sick and why maintaining positive building pressure is so important in prevention.

What Makes a Building Come Alive?

First, consider what may make your building come alive (or ultimately “infect” it):

  • Supplies
    The products you bring in (from any point of origin) may have outside contaminants or be perishable. As you know, perishables may emanate odors or fumes.
  • Chemicals
    You must account for chemicals or cleaning supplies in their controlled rooms (where exhaust is extremely important). 
  • Restrooms
    Consider the restroom facilities. Restrooms, especially those open to the general public (i.e. in a lobby area) can encounter high volumes of traffic and behaviors that may not meet sanitary standards. 
  • HVAC System(s)
    Your HVAC system is a key element bringing your building to life. With proper cleaning and maintenance, they are designed to provide comfort on demand. Heating and cooling are crucial amenities that have grown to be a must-have and are mandated by federal and local guidelines. 

When you take all these factors into account, it’s easier to understand how a building can become “sick.”

Sick Building Syndrome symptoms

Facility Managers: How to Prevent Sick Buildings

So how can a facility manager or building owner help to prevent sickness in a facility? As a professional in the HVAC industry, my primary goal is to earn your trust to maintain the wellness of your building’s HVAC system. Think about it — you can’t control others’ actions. There is no way to determine someone’s state of health as they are in your establishment. But you can control the HVAC system and make sure it is properly maintained to be a healthy system!

A little-known fact about HVAC systems that I will stress the importance: FRESH OUTSIDE AIR IS NEEDED TO MAINTAIN A POSITIVE BUILDING PRESSURE AT ALL TIMES. What does this mean, and why is it important?

  1.  Your restaurant, retail store or office building, has many moving parts to bring it alive, has to breathe. Like any living thing, it requires oxygen to replace the carbon dioxide. The equation should result in bringing in a greater amount of fresh air than the carbon dioxide, chemicals, fumes/odors, and cooking effluents that the building creates. When this happens, there should be a slight positive pressure from the inside of your establishment that pushes outward at your doors and drive-thru windows.  A proper HVAC test and balance (TAB) by an NEBB-Certified firm like Melink can help you achieve this goal.  

  2. A common oversight that people make is assuming, “My building is positive. We’re in good shape.” But how sure are they that the lungs of the HVAC system are clean and free of operational damages? Many times, I have encountered damaged and clogged filtration components within an HVAC system that may lead to costly repairs to your equipment and structural damages:
  • Clogged or missing outside air intake filters
  • Clogged, missing or inadequate air filters
  • Clogged evaporator and condenser coils
  • Clogged and inadequate fan blower wheels
  • Mold and mildew
  • Trapped small animals that lead to contaminations
  • Contaminated duct work that eventually shows up on the supply, return and exhaust grilles throughout the establishment 
Checking HVAC ductwork for positive building pressure

All these issues work together to create a sick building.  The opposite of positive pressure is that dreaded negative pressure. Every time your facility’s doors open, all of the outside air conditions are sucked into the building.  These elements can be hot or cold air, humidity, airborne pathogens, and odors. The humidity attaches to the chilled supply diffusers and grilles, creating moisture buildup that drips onto your floors, tables, customers, and clients.

Checking HVAC filters for positive building pressure

Of course, it’s not feasible for a facility manager to know the ins and outs of every HVAC system of every facility he/she manages. So let us do the work for you! Melink Corporation’s T&B technicians can be your eyes and ears to help your facilities maintain positive building pressure. We are an army of application engineers with skilled LEED and NEBB certifications. Our company is nationwide and has more than 30 years of experience. Along with services that will help you on your way to a healthy building, we offer a monitoring system and demand ventilation systems that will alert you when problems or concerns arise.  These services, along with reliable routine maintenance will minimize uninterrupted service to your most important people. We can help you protect your customers, employees, and outside partners from sick buildings.

Get A Pulse On Your Building

In today’s world, we are surrounded by smart phones, watches, cars, and other devices that are becoming further integrated into our lives. These smart sensors and technologies are helping day-to-day tasks become more efficient. To improve energy efficiency in commercial buildings and restaurants, these smart sensors and technologies can be applied in a similar manner.

Like a Fitbit that monitors and trends personal health metrics, sensors within a building can monitor and trend overall building health. With these smart sensors, important building health metrics, like relative humidity, CO2 levels, temperature, and pressure, can be measured to paint a picture of building health and HVAC performance. With data from the sensors, facility managers can identify improvements regarding building health, energy efficiency, and occupant safety and wellness within their building. PositiV, Melink’s exciting innovation in the world of building health, equips facility managers and building owners with a tool they need to verify building health and HVAC performance.

There are a variety of tell-tale signs of an unhealthy building like wet, dripping diffusers from high humidity, lower occupant cognitive ability from excessive CO2 levels, or a strong incoming draft at an open door caused by improper pressure or HVAC balance. These problematic unhealthy building signs can be addressed before becoming a costly, major issue. With building performance data, a facility manager or building owner will easier understand when building health begins to decline and identify corrective actions for the issues before they cause further problems.

A Fitbit won’t directly prevent a heart attack or make someone healthy, but it does arm its wearers with knowledge that is needed to live a healthier lifestyle. Similarly, building sensors won’t make a healthy building space, but they will equip its users with the information needed to create and sustain a healthy building space. It’s up to the manager or owner to take necessary corrective actions, but providing the data to help them make the proper decisions is the first step to improving overall building health.

Healthy Buildings & Employee Performance: The Next Revolution ?

Do you want to optimize your employees performance by 299%?  Increase cognitive ability in strategy development by 288%?

Yes! Of course, we all would love to fully optimize ourselves and those around us to maximize our potential and impact on the world.  What if the answer was all around us, literally allowing us to live, and also invisible.  According to new research focused on indoor air quality in the work place, there is a tremendous opportunity to move beyond “green” buildings and ensure we work in “healthy” buildings. 

Source: Natural Leader: The Cogfx Study

The COGfx Study, while limited to 24 participants, demonstrated that improved indoor environmental quality doubled cognitive testing results in buildings with enhanced ventilation versus conventional buildings.  The study distinguished between three building types; Conventional, Green, and Enhanced Green.  Within these building types the focus benchmarks were Carbon Dioxide levels in parts per million (ppm), ventilation rates expressed in cubic feet per minute (CFM) per person, and Volatile Organic Compounds (VOC) in micrograms per cubic meter. It’s also worth noting that building used was already a LEED Platinum certified facility, thus there’s likely more room for increased scores when comparing older existing buildings.

Source: Natural Leader: The Cogfx Study

The study explores the decrease in energy efficiency, which could be viewed as a negative, however relative to the increase in employee productivity and lost time due to sickness the savings can be dwarfed.  The noted increased cost per occupant in energy consumption is $400/year, however the study suggest a 6 x return in sick leave reductions alone relative to the increased energy cost.  Factor in the potential for increased productivity for one of the biggest operational cost for any company, the people, and the energy penalty is worth the investment.

While Melink is focused on energy efficiency, we’re also not blind to the impacts of IAQ and built our corporate HQ as a LEED Gold facility, later upgraded to Platinum.  In addition to the LEED standards, we also monitor in door CO2 levels via sensors and increase ventilation rates via a HVAC purge sequence once the room exceeds 800 ppm in CO2.  On average, the general office area CO2 levels hover around 600 ppm and are aided by the addition of live plants which produced an average drop of 100 ppm in CO2.

This focus on IAQ has led us to the development of a new product, Melink PositiV, to help ensure proper positive building pressure and CO2 levels in commercial buildings. The aim is to provide a simple solution for one of the biggest problems in all buildings, restaurants and retail locations; negative building pressure.  The standalone device will monitor pressure, temperature, relative humidity, and CO2 levels and provide a picture of building health and trends.

Top 5 Negative Building Pressure Problems

The difference between outside air supplied to a building and air removed from inside a building is the building pressure.  Typically, a slightly positive (or more air being supplied than taken out) building pressure is wanted for most buildings.  Negative building pressure can cause many issues for customers from high energy costs to hot and cold spots in a building.  Here are the top five problems a building with negative pressure can experience:

  1. Difficulty Opening and Closing Doors:

One of the first signs that a building is negatively pressurized, is when the front door is not easily opened.  After finally opening the door to a negatively pressurized building, a large draft will be felt on your back as the door is slammed closed.  Because buildings are typically designed to be positively pressurized, you should feel a soft gust of air blowing outward when this is set properly.

  1. High Humidity:

If your building is negatively pressurized, the building will pull in unconditioned outside air through all openings including doors, windows, and other leaks in the structure. This is very noticeable in the summertime when outside humidity is especially high.  This can cause mold or mildew in the building.

  1. High Energy Costs:

Studies have shown that correcting negative building pressure can save a facility owner as much as 20% on their HVAC energy costs.  By ensuring your facility has a positive building pressure, you are avoiding unnecessary costs and maximizing comfort in the facility.

  1. Outside Debris:

In a facility that is negatively pressurized, owners are more likely to see outside debris being pulled into the facility through various openings. These items include, leaves, flies, dirt, as well as smells brought in from outside.  In many facilities, this could create major issues with production as the outside debris could be contaminating the products.

  1. Hot and Cold Spots:

Another symptom commonly noticed in buildings with negative building pressure is noticeable hot and cold spots that are created by the disrupted airflow.  This could cause the customers to become angry because they can’t reach a comfortable temperature in the building.  In a restaurant, this could also cause food at the counter to become cold.

Talking to Kitchen Staff About Restaurant Air Balance

Muppet chef

Regarding restaurant air balance, negative building pressure costs restaurant facility managers thousands of dollars every year.  Uncomfortable kitchen staff, as well-intentioned as they may be, are often instigators of a facility’s air circulation becoming off balance.  Hot and bothered, they’ll tinker with the thermostats or other HVAC components in an effort to come into agreement with the air they are working in.  The issue is that most kitchen staff aren’t aware of the sensitivities of a balanced HVAC system and may make an adjustment that throws the system into inefficient operation, causing the entire operation to cost much more than necessary.

During your next site visit or conversation with on-site managers, restaurant facility managers should take a moment to explain the basics of air balance to kitchen staff.

Here are some points to explain:

1. The single most important thing to explain is that HVAC equipment works as “one system.”  What happens in the kitchen can and will affect the comfort in the dining areas, and vice versa.

Kitchen hood air transfer graphic

Graphic provided by Trane

2.  Explain basic building pressure.

  • Building pressure is a large factor of customer comfort, kitchen hood smoke capture, condensation issues, energy savings, door pull issues, insect issues. etc.
  • Kitchen airflow is the largest contributing factor to the overall building pressure.
  • High velocity airflow near kitchen hoods (like from a portable fan) can adversely effect the ability of those hoods to capture and remove heat and smoke.

3.  Emphasize regular cleaning of grease filters.

  • The kitchen staff and/or the building owner should ensure that all kitchen hood grease filters are being periodically cleaned.
  • They are in place to protect the exhaust duct work, exhaust fans, and the discharge area of the exhaust fans, which is typically the rooftop.
  • Grease filters can quickly become clogged if not thoroughly cleaned on a regular basis. Also, these should also be replaced immediately if they are damaged.

HVAC cover

Hiring an experienced and professional TAB firm to perform a test and balance on your HVAC system periodically can provide confidence that your systems are balanced and operating properly.  This will ensure that your kitchen staff is operating under the best conditions and that your customers are comfortable.