There’s more to the sticky hot air of summer and the chilly breezes in winter than you might think. Besides making the barn occupants uncomfortable, these conditions affect the health both of your horses and of your barn. But there is a way to help.
The perfect barn uses a system of vents that relies on nature to keep its occupants cool and breathing fresh, dry air throughout the year. That
continuous air exchange happens because of convection, which keeps drawing hot, stale air out of the barn and replaces it with cooler air. And, in climates where the mercury dips below freezing in winter, that same system should work without creating cold, unhealthy drafts. So, if you’re not dealing with a perfect barn, installing ceiling fans can go a long way toward maintaining relatively dry and comfortable air in your barn.
That’s good for two reasons. First, horses are prone to a number of respiratory ailments that can be carried by humid, dusty and stale air. Second, the moisture created by breathing horses and other activities that take place in the barn often condenses on metal and wood and if not removed can lead to rusty and rotten beams.
“Normally,” says Todd Gralla of Gralla Architects, “we’ll install fans to aid the convection process.” His company has designed horse barns and riding arenas around the world, but, he says, most of the barns he’s designed that get extra help from ceiling fans are located in hot, humid regions where it is critical to pull hot air out of horse stalls.
Nature at Work
In cooler climates, where temperature differences between the air that exists inside and outside of the barn are greater for long stretches of the year, nature has an easier time removing hot air and replacing it with cool. That’s why most barns have some type of vent or sequence of vents in the roof peak or at its ends.
Without getting deeper into the science, suffice it to say that the speed with which air is exchanged by convection slows greatly in warmer temperatures. That’s why, if you cannot rely on summer breezes for help, a system of properly sized and placed ceiling fans can help.
The Right Fan for the Right Purpose
Though barn builders and architects seem divided pretty evenly on whether fans should be used to blow a breeze onto horses or draw hot air out of their stalls, they all agree that high-output industrial fans that are sealed against the elements should be used in barn environments.
“The key,” according to Steve Ates, a dealer of pre-fabricated MD?Barns in Mississippi and Arkansas, “is going to a higher-quality fan than people think they need.” He says that a $145 industrial ceiling fan that is properly sealed against dust and debris will last at least four times as long “as a $50 model from Home Depot.”
Typical industrial ceiling fans vary widely in price, and range in diameter from 32 inches to 60 inches, with some models aimed at cooling large, open expanses with blades made of aluminum, plastic or stainless steel. Other components are made of plastic, fiberglass and steel and are often encased in protective PVC sheathing. Northwest Agrifan has a five-foot diameter and uses three blades. It is said to adequately service a 2,400 square foot area. The $210-fan is appropriate for open areas—perhaps in aisles—and only draws 0.71 amps of power. Other makes include Airmaster, Canarm, Craftmade, Emerson and NuTone. These manufacturers make fans with three, four, five and six blades that operate at high speeds to extend their effective ranges. Many are available with multiple speed settings that can be controlled manually or automatically (via a thermostat, for instance). A number of them have reversible rotations so they can either blow down or pull air up.
All these fans can be run on a typical 20- or 30-amp circuit. But industrial models are heavier than ceiling fans manufactured for home installations, which means they need to be mounted to a barn’s structural elements—either a ceiling joist or a roof’s rafter. Electrical codes generally require the junction boxes to be connected directly to structural elements when installing an industrial fixture anyway, and the fans usually mount with either two heavy-duty J-bolts or U-bolts. Most are also equipped with steel safety straps to guard against a fan falling to the floor and every builder contacted said a strap should be added if the units aren’t already equipped with one.
Finding the Best Location
The trick to properly outfitting a large open space like an arena is in figuring out how many fans are needed and how far apart they should be placed. This is where careful research will pay off. Each model will effectively circulate the air for a specific floor area depending on how high it is mounted. You need to determine the height at which you expect to hang the fans and then refer to the manufacturer’s specification tables to determine how many fans will be necessary. Then, the manufacturer—or your local commercial contractor—will be able to help determine their proper placement.
The job is a little easier in horse barns. Ates says he has installed one 32-inch fan over each stall to blow cooling air directly down on its occupant. Then, he’ll place other fans in the center aisle—one every four stalls.
The ceiling fans over the stalls are set so the blades have about 9.5 feet of clearance from the floor. And since most fan manufacturers offer a variety of down-rod lengths with their fans, adjusting the height of the units is a simple task.
But Todd Gralla, who agrees that one ceiling fan per stall is a good choice when the barn’s circulation needs to be helped, feels the hot air that collects in stalls placed along a barns exterior should be pulled up and out, not mixed around in a breeze directed at the horse. “Why compete with what’s happening naturally?” he asks. He also feels ground clearance should be about 12 feet.
“Determining whether certain stalls need fans at all is going to start with the barn design itself,” says Gralla. He points out that most newer barns are laid out with high, open rooflines, so stalls and aisles that run to the inside of a barn don’t need fans to pull hot air up. But stalls that run along the outside, where the roofline is much lower, might need help in directing hot air up and to the center of the structure. “It all depends on the construction,” he adds, explaining that a strong exhaust fan placed in one end of the barn near the peak can often help a great deal. Just make sure it’s installed with louvers that close when it shuts down and that there’s just one in one end, so two machines aren’t competing at opposite ends to blow out the hot air.
Scott Frankel, who owns and operates Scenic View Farms—a Quarter Horse facility—with his wife, Stacey Romano, DVM, in New Egypt, N.J., says their main barn has 56-inch ceiling fans over the aisle. The 56-stall barn is only a year and a half old and is both heated and air-conditioned. “We only use the air-conditioning in the barn on the hottest days,” says Frankel. “The rest of the summer, the fans do a good job circulating the air.”
Fans can also come in very handy in the stalls of horses that have a hypersensitivity to insect bites. In these cases, during summer, fans that blow a breeze directly into the stall will help keep biting flies and other insects away from the stall’s occupant and work in concert with any fly control program you might have in place.
Because there are a lot of barns out there of different designs that exist in different climates, each will have certain considerations. Because of this, it’s best to consult with a designer or contractor to determine whether your barn will benefit from fans above each stall or in the aisle.
And once you’ve determined that your animals will benefit from fans, improving the ventilation system in the barn will help protect the structure itself. Moisture is one of the barn’s worst enemies, and moisture from condensation can be insidious because it often occurs unseen and collects wherever hot, humid air is trapped. So, by ridding the barn of that air and continually replacing it with drier air from outside, you could be adding years to the barn and certainly saving on future repairs, to say nothing of improving the living conditions of its tenants.
Big Blades for Big Spaces
Naturally, the bigger the expanse you want to cool off, the bigger the fans or more numerous they have to be. With enough 60-inch models strategically placed you can help cool or ventilate a riding arena of any size. Southern California Edison (SCE) engineers, however, have been testing a new 20-foot diameter high-volume, low-speed (HVLS) fan and comparing it to conventional industrial ceiling fans used in agricultural settings. The new fan rotates at 50 rpm and uses only 400 watts of electricity—equivalent to the energy used by a typical 36-inch fan rotating at 800 rpm. The new fans were being tested at dairy farms.
In one milking shed, three HVLS fans with 0.5-hp motors replaced 16 conventional fans to determine how well they do the job while using less energy overall. What remains to be seen is how much energy can be saved over the long term and how reliable the new units are. Testing was said to have taken place through last summer. For more information on these new fans, visit www.sce.com and look under their “agricultural” heading. —JG