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Destratification Fans for Efficiency

Destratification Fans

Often uneven levels of air throughout a building can compromise comfort. Depending on the weather conditions, air temperatures can vary from 10-20 degrees due to air stratification or the layering effect of large pockets of air with various temperatures.

If you have experienced this in your commercial building or multi-level building, regardless of the HVAC system in place, the frustration is real.

What is stratification?

destratification fans

Every building has free space that contains thermal air layers with different temperatures called stratum.  Statum layers form gradient temperatures from floor to ceiling. As hot air rises, it spreads out across the area and becomes denser. It often becomes trapped at the ceiling level. When this happens, the floor level becomes cooler often decreasing the temperature by 1-2 degrees for every 3-foot increment of height. The higher the ceiling the cooler the floor level.

What does this mean for you? Your HVAC system will have to work harder and cycle longer to warm your space. When the HVAC system cycles down or shuts off, the area becomes cooler quickly overall rising utility costs, increasing the chance of premature equipment failure, and increasing energy bills.

What Is Destratification?

Once strata or layered temperatures form in a room or area, they become trapped at the ceiling level and need to be reversed. Destratification is the act of controlling and changing the natural process of thermal stratification. Because the outside weather conditions cannot be controlled, we use heating, ventilation, and air conditioning to help with destratification. Often, air conditioning systems need help. Destratification fans like energy-efficient HVLS fans and axial fans can help de-stratify the air and help with heating and cooling.

What is a Destratification Fan?

A destratification fan, typically suspended from the ceiling, acts as a ventilation and destratification device. Destratification fans are one of the most effective ways of solving stratification problems. They help circulate the air to provide a more even temperature. Increasing the comfort for the occupants.

When a destratification fan is used at the proper speed and direction, it will push the trapped heated air at the ceiling back down to the floor level. Overall, reducing the temperature differences between the highest and lowest points of the room. Increasing comfort in all areas and reducing energy costs by creating even temperature distribution.

What are the Benefits of a Destratification Fan?


Most generally, we think of ceiling fans or fans in general as a summer commodity. However, the value of a destratification ceiling fan is utilized during the winter months to increase heat. The airflow that is generated by a destratification fan provides the necessary force and circulation to move the warm and hot air from the ceiling back towards the floor. Increasing comfort overall.

When you have machinery and multiple people working in one area, the heat not only radiates from both the machinery and warm bodies. When that heat is mixed with the original heat source can often become too hot. HVLS fans can help not only distribute the warm air across the area and helps keep employees from overheating.

Reduced pollutants for cleaner indoor air

Everyone is thinking of ‘green’ – go green and save energy and the environment. Building managers and owners realize that green code compliance is essential. Stale, stagnant air is full of pollutants that can affect not only their products but their employees as well. Destratification fans can help with air circulation and minimize the risk of sick building syndrome (SBS). Sick building syndrome is often caused by stagnant, polluted air from chemical fumes, volatile organic compounds, pollen, and bio-aerosols. Sick building syndrome typically causes headaches, dizziness, and nausea while inside the building and resolves once outside the building. Using a destratification HVLS fan reduces pollutants from sitting at the floor area and increases ventilation, providing better air quality for employees and customers.

Reduce energy costs

With proper installation and used at the appropriate speed and direction, destratification fans contribute to increasing energy savings by helping to save up to 20-30% off heating costs for your commercial building or warehouse.

Eliminate condensation

If you have ever noticed water dripping from the ceiling or collecting on walls in industrial and commercial buildings or warehouses, more than likely, it is not a leak; it is internal condensation. Because temperatures fluctuate with colder air coming in contact with warm air or getting below the dew point level, a build-up of water or condensation happens. Condensation is a health hazard not only for you but for your employees, staff, and your product and machinery.

Destratification fans help reduce condensation by circulating warm, humid air that is trapped in the ceiling and pushing it towards the warmer ground.

What are the Types of Destratification Fans?

fans for efficiency

There are two types of fans used for destratification:

  • Preventative Low-Velocity Blade or Propeller Fan– Just as the name implies, these fans prevent destratification before it happens by operating continuously along with the heating system. With large impeller blades or paddles, and slower motor speeds, this type of fan requires less energy usage compared to standard speed fans.
  • High-velocity axial fan – Reactive fans operate at a much higher speed with airflows relative to the area they treat by pushing the air down to the floor level. Because of the higher fan speed, they are typically much louder. Generally, with the temperature set, they can change the temperature difference. Once the temperature reaches the preset level, it shuts off.

Both types are controlled by a thermostat and can work independently of the heating system, or along with it.

What to look for when purchasing a Destratification Fan?

Because of the many different types of fans on the market, it can be confusing on choosing which one meets your specific need. However, there are two things to consider, fan throw and fan spread.

Fan Throw is the distance air will travel from the fan to the floor. Terminal velocity ranges from 50,100 and 150 feet per minute. Most destratification fan specifications may indicate the Fan Throw at one or all three terminal velocity speeds.

Fan Spread is the amount of space a destratification fan will cover at a certain distance. This is the main thing to consider when deciding where to place the fan.


  • Mounting and ceiling height to minimize air pockets or drafts
  • How many fans needed for the area
  • Installation position for optimal air distribution
  • Easy maintenance access
  • Noise levels
  • The direction of airflow

Where is the best place to install a destratification fan?

The ideal location for installation is in high-traffic areas. The space outside of the fan spread should have minimal obstructions from equipment, machinery, or inventory storage that limits the fans’ range from reaching the floor level. As an installation best practice, install the fans away from walls by half a fan spread, and a full fan spread from other fans.

Regardless of a new installation during building construction or retrofit installation to an existing building, leave the job to professional installers. This will deliver optimal performance.

Destratification Fans: How Sender One Quietly Climbed to the Top Levels of Comfort



 Imagine taking your body to its limits by climbing a 60-foot vertical wall in an attempt to reach the top of a mountain. You finally get to the peak and look around expecting to quietly take in the view and feel a cool mountain breeze. Suddenly you hear the high-pitched buzz of a high-speed fan motor and instead of that gentle breeze, high winds are nearly blowing you off the mountain. Sender One Climbing Gym - a premier rock climbing gym in Los Angeles, CA - has gone to great lengths to make sure that the moment climbers reach the top of their indoor climbing walls is as comfortable and quiet as possible.

A big reason behind the minimal noise and comfortable climate in Sender One’s climbing space is their use of big commercial fans in combination with small destratification fans. This combination creates the optimal airflow needed to help climbers reach their peak performance.

A Good Tandem Equals a Good Climb

Sender One

Comfort was a key factor to address in Sender One's design process. The facility has multiple climbing walls that simulate large mountainous ranges. By using big commercial fans in combination with small destratification fans,  Sender One was able to achieve balanced airflow throughout the whole climbing gym.

“The climbing gym is a unique space, and with 30,000 square feet to cover and 3 different ceiling heights, the client was looking for an effective and economical way to promote circulation.  The combination of HVLS fans for broad/general coverage and small destratification fans for spot cooling in tight areas provided the perfect solution". Chris Westberg, CEM - Warehouse Solutions Specialist | MacroAir Sender One Project Distributor


What are destratification fans? Destratification fans are small fans with cannon-like frames that shoot air down to the ground. The shape of the fan is designed to push air directly into concentrated spots.

Why destratification fans work better with big fans: While destratification fans alone can help with distributing air in concentrated areas, there is no means of mixing the air and moving it throughout a space. In the graphic animation below you can see how large, minimal noise fans actually distribute air more efficiently than destratification fans alone. Big commercial fans in combination with small destratification fans can act as the perfect complement to each other

“The reason we have Zoo Fans (destratification fan vendor) is we think they complement the MacroAir fans. Zoo Fans are made specifically to destratify while we have MacroAir fans for creating turbulence / air flow, ie breezes. Zoo Fans on their own do little to create a breeze unless you’re standing directly under them”. – Wes Shih, COO, Sender One Climbing Gym



It Should be Quiet at the Top

Small industrial fans moving air at high speeds can reach noise levels of around 80 decibels. That’s noisier than a bulldozer or an ambulance siren! In fact, several of these units used together will create a serious noise pollution problem. The noise becomes problematic for climbers trying to achieve a moment of workout Zen. It can also be challenging for employees trying to stay productive throughout the day.

How loud is too loud? According to the American Speech Language Hearing Association, sounds at 85 dBA can lead to hearing loss if you listen to them for more than 8 hours at a time.

Why are big ceiling fans so quiet? One of the many benefits of using a big commercial ceiling fan is the extremely small amount of noise that it produces while operating. Unlike HVAC systems and small industrial fans that require several noisy parts or a large motor, big ceiling fans are built to improve airflow at a low speed. This in turn has a quieting effect while providing high volume airflow for the spaces in which they operate.

Tell us about your experience with small destratification fans paired with big ceiling fans! Do you notice how quiet big ceiling fans are?  Leave your comment below!

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