How to optimize the airflow in your barn, whether you have an existing structure or are starting from the ground up.

All living creatures need good quality air for optimal health and well being. This can become more of a challenge when housing a number of animals in an enclosed area. Particular care needs to be taken to ensure proper airflow is in place.

While keeping horses outside 24/7 might be optimal, it is not always possible. Some modifications to your existing barn, or pre-planning of a new structure, will help keep all its occupants, horse and human, healthy and happy.

The importance of proper airflow Nora Wolske of Canarm writes: “In addition to maximizing air quality, proper airflow and ventilation also play an important role in:

• improving environmental conditions (odor and humidity control)

• preventing the buildup of air contaminants such as ammonia, mold and dust

• providing a cooling breeze in warmer temperatures

• minimizing building deterioration problems such as rotting structures due to condensation

• ensuring a comfortable and healthy environment for both your horses and workers.”

Airflow also affects effective temperature and temperature control within the facility – important factors in areas with particularly hot or cold seasons. Cold is not necessarily as much of an issue as overheating. “Undue heat stress can cause reproductive issues, lameness and performance problems,” says Adam Hatton of Big Ass Fans.

Barn Design for Optimal Airflow

When developing a barn, there is a common thought that these buildings should not be airtight. But there is a difference between what many people consider “airtight”, and controlled airflow. “A controlled airflow is important to provide good quality air for the horses,” says Nora. “Airtightness is important to create static (negative) pressure that allows proper control of how and where the air enters and flows through the building. Most people do not realize that all the fans do is create (negative) static pressure in the building. It is the air inlets/ openings that control where the air enters and how it flows.”

In designing a new barn, consider the following:

• Arrange things so that hay storage is not above the horse stalls. This can allow for higher ceilings to encourage good circulation, while not obstructing airflow. Ideally, ceiling heights should be no less than 10’ to 12’ to ensure that any ceiling mounted fan is well above the range of your horse’s head.

• Since warm air, and with it, stable allergens and moisture, rises, it makes sense to include venting through the roof. When designing or fitting your barn with ventilation systems, ensure that the chimney exit extends at least one foot above the building peak so the stable air is vented outside and not released into the loft/attic.

• When looking at stall design, leave the top third of the stall partitions open with grillwork so as not to obstruct airflow.

Retrofitting Your Existing Barn

If you have an existing barn you are looking to improve the airflow in, your easiest solution will be to use fans. “Large diameter, low speed fans homogenize the air, making it consistent throughout and helping to disperse odors, ammonia and other gases that otherwise gather in the horses’ breathing zone,” explains Adam. “A properly built large diameter, low speed fan can improve ventilation by 20%.”

Proper fan placement is important for your efforts to have a maximum effect. “To ensure that fresh air gets to every horse and can move freely between stalls, circulation fans can be wall mounted or hung from rafters, or models with a pedestal can be conveniently situated where needed and readily moved,” says Nora. “However, unless the fan is placed by a window or opening it will only reuse existing air in the barn.”

Selecting a Fan

Barn fires are every horse owner’s worst nightmare. It is important that any appliance you select for your farm is meant for that particular setting. Residential fans don’t make the cut. “Small, traditional inexpensive box fans have multiple hazards,” cautions Adam. “While they might be fine in a residential application, they aren’t made for dusty environments or where excessive cords can cause trip or chew hazards. Most barn fires occur from outlet plugs, making box fans even more dangerous. It’s also important to have a fan that can withstand the environment you’re trying to put it into, whether it be a non-vented type gearbox that can withstand dusty environments, or a proper IP or NEMA rating on the motor and control system.”

“The operating conditions are different in residential and agricultural settings,” adds Nora. “Barn environments, for example, have significantly higher levels of moisture and dust. Most residential fan motors are vented, allowing dirt and moisture inside the motors, while agricultural or industrial fan motors are totally enclosed, ensuring a longer life in these harsher environments. Purchasing agricultural fans will provide you with several years of safe, dependable use.”

Good quality air is one of the most basic things you can give your horse to ensure a long and healthy life and optimal performance. If you need help assessing your current barn, or in planning a future structure, get in touch with an agriculture ventilation specialist or company in your area – most will be more than happy to help guide you.