Air Blue - How HVAC Design Can Enhance Airflow in High-Rise Chicago Apartments
Per the National Fire Protection Association, a high-rise apartment building is at least seven stories, which means a rise of at least 75 feet over the lowest level. Many people live within these buildings, making them useful for housing a substantial population without needing a massive amount of land. The higher floors also provide breathtaking views of the area.
Chicago has close to 1,400 high-rise buildings.
The problem with high-rise apartment buildings is that you have rows of apartments stacked on top of each other. Without an effective ventilation system, people end up breathing stale air. It gets sweltering as hot air and humidity rise. All of this impacts your residents’ health and happiness. An effective, efficient HVAC system enhances airflow and keeps your building’s residents comfortable. It all starts with the right design.
What Are the Airflow Challenges in Chicago High-Rise Apartments?
A high-rise apartment building can be any shape, and that’s one of the challenges. If you start getting into irregular shapes, ducts may need to take unusual angles. While the ductwork will go in a straight line for vertical rises, a duct in an octagonal building may take a 45-degree angle. That angle is going to impede airflow.
Even if you have straight ducts, airflow can dwindle as it gets farther from the fans. An apartment closer to the ventilation fans receives more cool or warm air than someone at the end of the duct.
Another factor is the pressure between stories. The air pressure in street-level apartments is lower than what people in a penthouse suite experience.
Space may not be available for the system of your dreams. Structural integrity is a primary consideration when building a high-rise apartment building. The building’s structure may not provide the room you want for the HVAC system you desire. Expertise in HVAC design is important to ensure that ducts and HVAC equipment enhance airflow.
If airflow isn’t optimal in every apartment and on every floor, someone is going to end up too hot, too humid, and generally miserable. That person who is dealing with increased humidity and mold won’t want to pay the same rent as someone not going through these issues.
Despite the challenges, the Illinois Department of Public Health has guidelines in place for air quality and climate control. A building should have carbon dioxide levels of no more than 800 ppm. Carbon monoxide levels should not exceed 9 ppm. If levels are 100 ppm or higher, the building must be evacuated until the issue is fixed and levels decrease. Hydrogen sulfide from sewer gas needs to be less than 0.01 ppm. Other recommended levels are as follows.
- Formaldehyde – No higher than 0.03 ppm
- Humidity – 20% to 60%
- Nitrogen Dioxide – No higher than 0.05 ppm
- Ozone – No higher than 0.08 ppm
- Particulates – Under 3 microns (respirable)
- Radon – Less than 4 pCi/L.
- Temperature – No higher than 79º F in the summer and no colder than 68º F in the winter.
- Tobacco – Do not allow indoor smoking or provide an HVAC system that vents the tobacco fumes from the building’s main HVAC system.
Filters do a lot to help with air quality, but airflow ensures contaminants move through filters. That gives your residents the clean air they need.
The Top HVAC Design Strategies That Improve Airflow
How do you ensure airflow is correct and protect your residents’ comfort levels? One thing to consider is if you should have a central HVAC system for the whole building or individual systems for each apartment and common area. While a central HVAC system is easier to maintain, comfort levels are easy to achieve with individual systems. Getting residents to keep them maintained may be more of a challenge, however.
Ventilation is tricky in a building with seven or more stories. Ducts and vents need to be carefully designed so that the airflow is the same, no matter how far an apartment is from the HVAC equipment. Those ducts should be sealed to prevent any leakage. Consider demand-controlled systems that increase or decrease temperatures when an apartment is empty for an extended period. Variable-speed blowers can increase or decrease fan speeds to match demand.
A system has to be pressurized correctly. It’s something that one of our Air Blue trained commercial HVAC installer and maintenance technicians should during yearly cleanings and inspections.
Take advantage of temperature differences between inside and outside air. Energy recovery ventilation (ERV) technology captures energy from the hot exhaust from your high-rise building and uses that energy to cool or heat the air that’s circulating around the rooms.
Lowering humidity is also important. Desiccant dehumidification uses materials that absorb moisture from the air, which pre-cools the air and lowers the amount of work an AC system needs to do.
Keep your system well maintained. If you’re remembering to replace filters each month, inspect the system regularly, and hire professionals to test the pressure and clean coils and ducts, you keep the HVAC system running efficiently.
Finally, you need to set up multiple zones in your building. Instead of having a few zones for the lower, mid, and upper levels in your building, you could have one zone for each floor.
What’s the Cost of Improperly Working HVAC Systems in Chicago?
Meeting city codes regarding air quality isn’t enough. If tenants aren’t happy with the air quality in their apartment, they’re going to complain. They may file complaints with the city or refuse to pay rent until improvements are made. Don’t discount the value of keeping tenants happy. The City of Chicago charges fines of $500 to $1,000 per day, per apartment for inadequate heat.
While a commercial HVAC system can be expensive, modern technology makes systems easier to monitor and maintain. They’re also better at minimizing electricity and heating fuels. Upgrading an old system can save you thousands in heating and cooling costs. Just a light commercial heating and cooling system cuts energy bills by 6% according to Energy Star. Imagine the savings if you have a system designed for your high-rise apartment building.
Talk to the team at Air Blue Heating and Cooling about your Chicago high-rise apartment’s HVAC system. We have more than 20 years of experience installing and servicing commercial heating, ventilation, and AC systems. Schedule an appointment online or ask us for a free quote.
