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Why is Ceiling Fan Clearance Height So Important?
Proper installation of your HVLS ceiling fan is essential. It ensures your fan is running at peak performance to help keep you cooler, healthier, and safer. A crucial part of the installation process is knowing the appropriate ceiling fan clearance height. There are many factors to consider including: distance from ceiling, floor, and wall, building codes and fire safety, and national standards. The fact is that the clear definition of ceiling fan clearance height requirements differs slightly between different codes and standards, along with each unique building/installation. This blog will break down all you need to know about ceiling fan clearance height to ensure optimal airflow, comfort, and safety.
Ceiling Fan Clearance Height Standards
According to the DOE (Energy Star), “ceiling fans should be installed or mounted, in the middle of the room and at least 7 feet above the floor and 18 inches from the walls. If ceiling height allows, install the fan 8 - 9 feet above the floor for optimal airflow.” In addition, most large industrial ceiling fans (HVLS fans) require 38-96 inches of clearance from the ceiling. To allow for this clearance, guy wires are typically needed at installation.
HVLS ceiling fans ranging in size from 6-24 ft in diameter do have a higher clearance requirement. MacroAir fans have a minimum height requirement of at least 10 feet above the floor. Plus, most fans have a 3 ft drop standard, meaning your ceiling height must be at least 13 ft. Many models can be shortened to a 2 ft drop standard. The AVD370 can go as short as a one ft drop standard.
For safety reasons, you must make certain that fans are positioned so that blade tips are at least 3 feet away from any area where a person may be able to extend outward to reach them.
Can Ceiling Fans be too high or low?
Simply stated, yes, ceiling fans can be mounted too high or low.
In fact, how close the fan is to the ceiling is very important when the aim is to properly and effectively distribute air within a space. If you mount it without a drop rod, that is called a “ceiling hugger.” The problem with that is that air can’t come from the top of your ceiling and into the blades of the fan. If you instead drop the fan, you allow the air to come in and go through the fan. The result is better air movement.
However, installing the HVLS fan high off the ground has advantages. For instance, if your HVLS fan is mounted at 20-feet, you would reach people as far as 70 feet away. But as you come closer to the ground, this diameter is reduced. A good demonstration is when you have a fan inside a cone. As you raise the fan, the cone spreads out; if you lower the fan the cone shrinks.
How far from the wall can your ceiling fan be?
Your fan should be 1.5 times the diameter of the fan from the wall. So, for example, if my fan was 6 feet in diameter, I would take 6 x 1.5 = 9. That means my ceiling fan should be 9 feet from the wall.
When determining how many fans you need in your facility, consider the layout of your facility, since large spaces will require multiple fans. You also must think about the spacing between those fans. Depending on the diameter of your fan, you will take that diameter and multiply it by 3 to find the distance between fans. For example, if the diameter of my fan was 6 feet, I would take 6 x 3 = 18. That means there should be 18 feet in between my fans.
What to consider when buying your large ceiling fan?
When shopping for a large ceiling fan, there are two key components to consider in helping you determine the appropriate size of a ceiling-mounted fan for your space:
- Size of the room
- Height of the ceiling
If you have a 16-foot ceiling, the fan is going to drop to 13 feet automatically because of clearance. On a smaller fan, this is fine. But on a larger fan, you need as much as a 5-foot drop. Already, the fan is brought down to 11-feet.
Fan expert, Jason Hornsby tells us that “when you don’t have a high ceiling but have a lower ceiling height, a short blade HVLS fan would work better. The reason is that small fans have a higher RPM (Revolutions per Minute) which increases velocity.”
The larger fan revolves much slower. It has a larger volume, but a lower speed. This is important to note because if you select too large of a blade size for your space, the fan might actually underperform compared to its counterpart.
Sprinkler and Safety Standards
The National Fire Protection Agency (NFPA) spells out standards for how HVLS fans should be installed in buildings with sprinklers in its NFPA 13 document. The NFPA 13 says that the vertical clearance from the HVLS fan to sprinkler deflectors must be a minimum of 3 feet. You can read all requirements for installation of large ceiling fans in buildings equipped with sprinklers in the list of NFPA codes and standards. In addition, a recent MacroAir blog outlines the key guidelines for placing HVLS fans in sprinkler protected buildings.
In addition to NFPA 13 guidelines, HVLS ceiling fans should have proper safety components included with each installation. MacroAir includes guy wires to ensure the fan is safe and secure no matter the application.
Let MacroAir Help You Get Started
The above information is a great place to start. However, the clear definition of ceiling height requirements differs slightly between the DOE and NFPA and with each unique building/installation. Therefore, the best option is always to contact the experts within the fan company to help you make the most appropriate decision in regards to ceiling fan clearance height. MacroAir’s experts are always available to answer any questions you may have in regards to clearance and spacing requirements for your fan. They will help you pick the fan that is right for you and make sure it is installed and running at optimal level to help keep you cooler, healthier, and safer.
Contact us today to speak with a knowledgeable customer care representative.
Let us help you get started the right way.