What size fan do I need for my barn? Answers to Protect and Care for Livestock

The question: What size fan do I need for my barn to maintain a healthy environment? The answer, however, is more complex than you may think.

Barn fans are one of the traditional tools for maintaining good air quality for healthy livestock and hopefully keeping them cool in hot weather, as “air conditioning” a barn is rather impossible.

The truth is that while there are some things that fans can achieve, there are some traditional uses for which a fan is not practical.

We will explore the right sizes for the right jobs below; however, for some purposes, you simply need a better tool.

What Size Fan Do I Need For My Barn?

Let’s start with something a little different and explore the role that the fan can play in your barn. Typically, if you are looking for a livestock fan, you need to achieve several goals:

• Ventilation
• Circulation
• Cooling

Fans are adequate for ventilation and circulation. However, since fans don’t cool the air, they are not ideal for cooling. Lets look at ideal sizing for the first two, then explore the third.

What Size Fan Do I Need For My Barn for Ventilation

Ventilation fans bring fresh air into a barn while exhausting air from the barn. This helps supply animals with fresh air to breathe and reduces the risk of respiratory infections for your animals.

All animals need some degree of ventilation, but the amount of ventilation necessary depends on the type of livestock you’re raising. With different approaches to animal husbandry for each species, recommendations for animals are reported in different terms.

For cows, ventilation needs are reported in air changes per hour (ACH). For most cows, the recommended ACH is 40-60 in the summer and 4 in the winter.

For pigs, recommendations are in terms of cubic feet per minute (cfm) per unit. These recommendations vary based on the size and health of the swine.

For a sow with a litter, the advice is 20 cfm in cold weather and 500 cfm in hot weather. For nursery pigs, the recommendation is 2 cfm in cold weather and 25 cfm in warm weather.

For a horse fan, you want to make sure it’s delivering at least 25 cfm in cold weather, and 200 cfm in hot weather.  This should provide 4-8 ACH to help horses stay healthy.

What Size Fan Do I Need For My Barn for Circulation

The other purpose of barn fans is air circulation.

These fans ensure that there are no places in the barn where stale air is collecting. Circulation fans stir the air within the barn to make sure that all the air is being appropriately exchanged with the outside for all the stalls or pens.

Many professionally-designed ventilation systems incorporate circulation into their design. When you are getting a professional ventilation system installed, ask them to diagram the airflow through the barn to ensure you’re getting adequate air circulation.

For high-volume low-speed (HVLS) fans, you want to space them apart by about twice the diameter of the fan (e.g., 30-foot diameter fans can be spaced apart by 60 feet).

Not Adequate for Cooling

While the answer to the question of what size fan do I need for my barn is individual to the use and needs, often, you need a better tool than a simple fan. You cannot count on barn fans to cool your animals.

That’s because fans do not cool the air at all. They only move the air around.

People supplying ventilation systems will tell you that you need air to move at a certain speed to provide cooling for animals. However, it’s the same for animals as it is for humans – moving air will only feel cool if the air temperature is low enough.

Once the air temperature gets above 75° F, simply moving air starts to lose cooling effectiveness for animals, the same as for humans.

Under these conditions, animals rely on evaporative cooling (by sweating or wallowing), and the animal can start to feel stressed by the conditions. Worse, barn fans can actually increase the temperature in the barn, adding to animals’ stress.

For hot days, it’s important to have a cooling solution.

Evaporative Cooling Works for Livestock

Portacool portable evaporative coolers are an ideal cooling solution for barns. They can effectively cool air in hot conditions (even hot and humid conditions).

That helps your horses and other animals feel more comfortable in the barn, protecting them from heat-related illness and injury.

Providing cool, fresh air can help animals to feel more comfortable. Circulation fans can help distribute cooled air throughout the barn.

While your animals won’t need as much ventilation when you’re using a Portacool, you also don’t have to worry that the barn doesn’t hold all the cool air, as the Portacool continues to supply fresh, cool air to maintain low temperatures even in a leaky barn.

To get a Portacool to help keep your animals comfortable, please visit a local or online retailer. If you are looking for a bulk order of evaporative coolers, please contact Portacool directly.