Air Curtains

Every open doorway is an invitation for outside air, dust, and insects to pour in, and that's exactly what an air curtain is built to stop. A focused stream of high-velocity air spans the opening, holding indoor temperature and air quality steady while people, forklifts, and carts pass through without a break in the barrier. Facilities that install one often cut the energy loss through that single doorway by up to 80%, which is why air curtains have become standard equipment in warehouses, retail entrances, food service operations, and anywhere else a door stays open for a good part of the day.

How Air Curtains Actually Work

Once you understand how an air curtain works, the rest of the buying decision gets easier. It comes down to a simple piece of physics executed at scale.

The Invisible Barrier

A blower pushes a focused, high-velocity stream of air straight down across the doorway, creating what's essentially an invisible barrier between conditioned indoor air and outdoor ambient air. People, forklifts, and carts move through it freely, while the air stream itself blocks that exchange. 

It's simple in concept, but the technology behind sizing and controlling the stream correctly is what separates a unit that actually works from one that just makes noise.

The Energy and Air Quality Payoff

Studies on doorway energy loss show air curtains can cut infiltration through an open door by up to 80% compared to leaving it unprotected, and many facilities see overall HVAC energy savings in the 20 to 30% range tied to that one entryway. Because the fix is relatively inexpensive and the losses from an open door are constant, payback typically lands somewhere between 6 and 18 months, faster than most equipment upgrades pay for themselves. 

Beyond temperature control, a properly sized unit also keeps flying insects, dust, and airborne pollutants from drifting through, which matters just as much in food service and manufacturing as it does for comfort.

Sizing Your Air Curtain

Getting the size wrong is the single most common mistake, and it's an easy one to avoid once you know what to check. A handful of factors determine whether a unit actually seals the doorway or just adds noise to the room.

Width

Width has to match or exceed the door opening. A unit narrower than the doorway leaves a gap on one or both sides, and that gap undoes most of the benefit. Wide openings sometimes call for two units installed side by side with no space between them.

Velocity

Velocity has to match the door height. Taller doors need a stronger air stream to make sure it still has enough force to reach the floor. A 20-foot loading dock door and a 7-foot storefront entrance are not the same sizing problem.

Heated or Unheated

Heated air curtains help retain heat in cold climates or on doors that stay open often through winter. Unheated units are the better fit for warmer regions, cold storage doorways where humidity control matters as much as temperature, or situations where pest and dust control matter more than heat.

Door-Activated Controls

A magnetic or door-interlock sensor that only runs the unit while the door is actually open keeps energy use, and savings, where they should be instead of running the fan around the clock.

Which Berner Line Fits Your Application

Berner has built high quality air curtains in the U.S. since 1956, and the lineup on this page spans five distinct product families, each built for a different environment. Matching the right family to your space is just as important as getting the width and velocity right.

• Low Profile: Suited to retail entrances and public-facing spaces where design and appearance matter as much as performance.

• Commercial: Covers the broad middle ground: offices, restaurants, and general commercial entries.

• Sanitation-Certified: Built for food service, food processing, and clean rooms with strict cleanliness requirements.

• Commercial High-Performance: Handles high-traffic doorways, loading docks, and other demanding industrial applications.

Common Applications

• Warehouses and dock doors

• Retail and grocery store entrances

• Food processing and sanitation-certified facilities

• Manufacturing plants with high-traffic openings

• Cold storage and freezer doorways

• Hazardous or combustible-dust environments

Why Shop for Air Curtains at Industrial Fans Direct?

Industrial Fans Direct has spent more than 20 years supplying ventilation and heating solutions to customers across the U.S. and around the world. Mechanical contractors, engineers, electricians, facility managers, and commercial building owners rely on us for the right air movement equipment and supplies, and we've built strong relationships with our manufacturing partners, including Berner, to keep pricing competitive and the order-to-delivery process painless.

What you're really buying when you shop with us is access to a knowledgeable, friendly customer service team that won't try to upsell you or push equipment you don't need. Our sales team doesn't work on commission, so we're focused on getting you exactly what the job requires, nothing more.

• Low Price Guarantee and volume discounts

• Free Shipping on most orders

• Non-commissioned experts who give advice, not a sales pitch

• 20+ years focused exclusively on ventilation

Need help with an order? Contact our team.

Frequently Asked Questions

Do air curtains work with the door open or closed? 

They're designed to run while the door is open, which is when infiltration actually happens. A door-interlock sensor is the standard way to make sure the unit only runs when it's needed.

How much can an air curtain actually save on energy costs? 

Studies show up to 80% less infiltration through an open doorway, translating to roughly 20 to 30% in HVAC energy savings tied to that entry point, with typical payback in 6 to 18 months.

Should I choose a heated or unheated model? 

Heated units offset cold air coming through a frequently opened door in winter climates. Unheated units are better suited to warmer regions or situations focused on pest and dust control rather than temperature.

How do I know what size I need? 

Match the unit's width to your door opening, at minimum, and confirm the air velocity is rated for your door height. Undersized units leave gaps that let outside air, insects, and dust straight through.