Air curtains, also known as air doors, are alternatives to traditional doors when creating a room that needs a specific climate, like a walk-in cooler at a restaurant. They include overhead mounted blowers on one or both sides, depending on their location and use. This makes an invisible “air barrier” between two spaces. A door made of air, if you will.

Air curtains are meant to keep contaminants like insects and odors from one space out of another space. They keep separate rooms at separate temperatures and humidities even as people move between those rooms. In some contexts, air curtains are paired with a supplemental, material door. You’ve likely seen them before — those doorways made of thick, overlapping strips of plastic? That blast of cold air that hits your face in a breezeway between two sliding glass doors?

Understanding the Functionality of Air Curtains

Despite the name, an air curtain is actually a device that creates an invisible barrier of high-velocity air over an entryway or between two spaces. This barrier effectively separates different environments without the need for physical doors. The primary components of an air curtain include:

  • Blower fans to generate a consistent stream of air
  • An air nozzle or plenum that directs the airflow uniformly across the opening
  • Control systems that allow for adjustments in airflow speed and temperature

When activated, the air curtain discharges a controlled stream of air, forming a barrier that minimizes the infiltration or unconditioned air, contaminants, and pests.

But where exactly have you seen these air curtains? And why would a business want an air curtain in the first place?

Where Can You Use an Air Curtain?

Ever worked in a restaurant that had a walk-in cooler or freezer? Have you ever been in a laboratory with cold storage? Businesses like these need efficient ways to get in and out of cold storage without wasting energy or compromising the temperature of that room. You wouldn’t want fresh produce or the active ingredients in a medication to spoil. A traditional door lets in air contaminants and can also compromise the temperature in these kinds of spaces.

But other businesses benefit from this efficient way to separate the environment of different rooms as well. Air curtains are frequently used in:

  • Commercial Entrances. Those rows of double sliding glass doors in retail stores, supermarkets, and shopping malls would absolutely sink a company in heating and cooling costs, not to mention let in all number of pests, dirt and debris if air curtains on either side didn’t stop them.
  • Industrial Facilities. Air curtains are used in warehouses and manufacturing plants to separate different temperature zones and prevent cross-contamination.
  • Cold Storage Facilities. Air curtains are put to great use in refrigerated rooms to minimize temperature fluctuations and reduce energy consumption.
  • Food Service Establishments. These are commonly found in restaurants and food processing units to deter flying insects and maintain hygiene standards.
  • Healthcare Settings. We also see air curtains used in medical contexts. they can be used to separate sterile and non-sterile areas in hospitals and laboratories, reducing the risk of contamination.
  • Zoos and Botanical Gardens. If you’ve ever been to a botanical garden, a butterfly conservatory or an aviary, you’ve probably seen air curtains there as well. Tropical birds or plants do not mix well with those from the desert. Often, in places like these with living creatures, they will even use double air curtains to ensure people don’t accidentally let a bird or a butterfly into the adjoining room.

What are the Benefits of Air Curtains?

Now, for any one of the above examples, think about the alternative- a traditional door- no blowers. This door may be heavy duty and have great insulating qualities. But still, there’s always the few seconds between pulling that door open, walking through and letting it swing closed behind you, that you are mixing climates between the two rooms. This isn’t good for overall energy efficiency, and with special products like produce, medication, plants, birds and insects, there is definitely a higher chance of putting these things at risk in just those few seconds.

Some other quick points on the advantages of air curtains in commercial doorways:

  • Lower energy costs because of control of air transfer between spaces
  • Lower overhead costs due to the building’s HVAC system working less hard, which means less use, less wear and tear, less maintenance, and
  • lower utility costs
  • Increasing ventilation and air circulation, creating a better environment for people in the building
  • Free traffic flow between spaces, ADA-friendly
  • Uninterrupted lines of sight, inviting feel for storefront doors
  • Reduced CO2 emissions
  • Greatly reduces smoke transfer in cases of fire emergencies
  • More available space on storefront entryways

Even if you have a breezeway with a door on each side to separate the spaces, you’re still losing temperature and humidity in that space between the doors. Air curtains and their overhead blowers drastically reduce energy loss and contamination risk. Thinking about it, you’ve probably seen them all over the place but weren’t aware of why. Now that you know, maybe the utility of an air curtain is something you might consider for your business.

Selecting the Right Air Curtain for Your Needs

When choosing an air curtain, consider the following factors:

  • Door Dimensions: Ensure the air curtain matches the width and height of the entrance for effective coverage.
  • Mountain Options: Depending on the space and design, air curtains can be mounted horizontally above the door or vertically alongside it.
  • Airflow Velocity: Select a model with appropriate airflow speed to counteract external wind pressures and effectively maintain the barrier.
  • Heating Options: Some air curtains come with heating elements to provide warm air during colder months.
  • Control Features: Advanced models offer programmable settings, remote controls, and integration with building management systems for optimized performance.