Airing Out Your Barn

Many agree that older barns are gorgeous, but are they good for horses? There are many issues to consider, such as construction, footing, layout, and safety. One of the biggest issues is ventilation--is your horse getting enough air?

Ventilation--What Is It?

Back in 1908, the Royal Army in the United Kingdom determined a rule of thumb that buildings should have eight to 10 air exchanges per hour. That means that all of the air in a building should be completely replaced every six to seven minutes. According to Larry Turner, PhD, Extension Professor and Chair of the Department of Biosystems and Agricultural Engineering at the University of Kentucky, this rule still holds almost 100 years later. Turner's work includes engineering, planning, design, and analysis of livestock environments and facilities.

Turner finds that the main problems with older barns are usually not enough outer openings, and ceilings that are too low. New thinking holds that barns should be built with no ceiling between the top of the stalls and the roof. If there must be a ceiling, have it over the aisle only. This way air can move unrestricted around the horses; older barns with low ceilings hold in too much air.

According to Turner, another ventilation problem with horse barns is the animal density--it is too low. When a herd of cows lives in a building, there are a lot of animals generating heat. This creates hot air, which rises. Cool air comes in to replace the rising warm air, and a circulation pattern is established. (This is called the "stack effect.") When a barn has one horse per 12-foot by 12-foot stall, there is not enough hot air to create this natural circulation.

The proper amount of air movement is two miles per hour, a small amount of airflow that should feel like a very faint breeze. Proper ventilation should prevent heat and moisture buildup. If a barn has too much of either, it very likely has a ventilation problem. In an older barn, this can lead to deterioration of the wood over time.

What horse barns need are adequate side wall ventilation, eave ventilation, and ridge ventilation to deliver fresh air to the stalls. New and fancy is not always the answer. "You'd be surprised at a lot of nice barns that are not designed very well from the ventilation standpoint," says Turner. "I'm always amazed when I see multi-million-dollar stallions being cooled by a Wal-Mart box fan.

"What I tell owners of horses is this: If you want to maintain that nice slick coat and you want to have that nice environment in the barn, it's pay me now or pay me later. You're probably going to have to provide some supplemental heat, and you're going to have to provide adequate ventilation in order to maintain the environment you want in the winter time. If you're not willing to do that, then you're going to suffer the consequences of having this damp barn with degradation of the facilities and also not the best environment for the horse."

Since a properly ventilated barn might feel colder to humans, Turner says it's a choice the owner has to make since horses are fine in colder weather. "In a barn, if you're breaking the wind but maintaining air temperature that's similar to outside, the horse is going to be fine. It's the people that complain."

What Are Older Barns?

For David Ciolek of Williamston, Mich., the way to understand older barns is to understand their history. His company, David Ciolek Barn Construction, does barn repair, straightening, conversion, and relocation.

"Large barns were never meant to store large animals," says Ciolek. Back when they were built, most large barns were meant to dry and thresh grain. Drying grain was spread across the big center floor. When stirred up, the undesirable parts--the chaff--was blown away from the grain. The large doors on either end of the threshing floor were adjusted to control the amount of breeze.

In the late 1800s, two changes to the farming industry changed the way barns were used. One, threshing machines did their work in the field. This eliminated the need for threshing floors and made grain storage more com-pact, freeing up storage space. Two, the dairy industry began.

When converted to house cows, the barns were made tighter and warmer. Contemporary thought held that this was the best way to keep animals. They did recognize that hay should not be stored with animals, so lofts were built to keep hay and feed away from the animals. Hay was dropped from the loft via a hay chute.

After more than 20 years of working on old barns, Ciolek is now seeing more and more older barns being converted to horse use. Although he works on all kinds of barns for all kinds of animals, horse barns have grown to almost 50% of his business.

"There is more of a new awareness on the part of the animal owner that fresh air is a good thing," explains Ciolek. So, he said, they understand that some kind of ventilation retrofitting is needed.

The loft usually is changed--a typical old eight-foot ceiling is too low for horses, and a 12-foot ceiling will provide better natural ventilation. A loft can be easily raised, since it is not original to the building. This might be the hardest part of reconstruction for the layman to understand. It's hard for them to see something as heavy and solid as an old barn ceiling and to remember that it is simply a later addition. Ciolek works under the assumption that clients will keep and use the lofts.

"These barns can be highly profitable," says Ciolek, mainly because of the lofts. By storing hay in the same building, owners save time and money. With enough space, they can either grow and store their own hay or buy an entire year's supply at once at a reduced price. Having hay above the horses also saves the owner time in feeding or money in labor costs if they pay others to feed, however owners should be aware of the chance of respiratory problems developing.

Ciolek reminds horse owners that renovating an old barn to house horses need not involve hordes of experts and cost millions of dollars. "I think in most cases what I find about engineers and architects is it's sometimes good to bring them in at the beginning for their information," he says. "Get two different opinions, and make your choices."

Ciolek feels that the chance to save an old barn is also the chance to save time, money, beauty, and history.

Ventilation and the Horse

Any improperly ventilated barn is bad for horses, but a badly ventilated older barn offers a few extra concerns. Melissa Mazan, DVM, Dipl. ACVIM, of the Tufts University School of Veterinary Medicine in Massachusetts, also traces the problems of older barns to their history. Mazan, who is Director of the Issam Fares Equine Sports Medicine Program, is board certified in veterinary internal medicine and her special interests include inflammatory airway disease in horses.

"People were usually trying for the optimum in storage and warmth, neither one of which is good for horses," she says of some older barns. "Barns were made airtight with small windows, small doors, and interior stalls. Airtight conditions can create mold and fungus. In an older barn, this means mold and fungus have had more time to grow. In addition, their use as storage spaces means that older barns are havens for leftover debris--old tack, machinery, ancient hay."

Mazan advocates removing hay from the lofts, as hay chaff and dust can filter down between cracks. Even the best of hay can have spores that could lead to heaves, otherwise known as COPD (chronic obstructive pulmonary disease) or small airway inflammatory disease (similar to asthma in humans). These tiny particles might be barely noticeable to the human eye. If you store hay in lofts, horses end up re-breathing hay particles as well as any mold or fungus.

The airtight approach to heat conservation was prevalent not terribly long ago, said Mazan. "Very few people, until I'd say the last 10 to 15 years, were thinking about good ventilation. I know that when I was growing up and showing horses, which is back in the 1960s and '70s, we used to batten up all the windows at night and make sure the doors were closed." Mazan now thinks just the opposite. "The best way for a horse to live even in this climate (Massachusetts), which is quite cold, would be a three-sided shed with good shelter from the wind. Not to be in a stall at all would be ideal."

Respiratory disease is an occupational hazard for many horses, says Mazan. "If you go to countries where hay is not fed and horses are kept outside, or even parts of this country like California where horses are more likely to be kept outside, the incidence of respiratory disease goes way down. A very large proportion of older horses have at least subclinical disease, if not overt disease where they are huffing and puffing. One of the major causes of declines in performance or inability to use an older horse--or sometimes even middle-aged or younger horses in this part of the country--is the way we keep them. And a lot of that has to do with poor ventilation in barns."

What can you do to make that lovely old barn horse-friendly? First open and widen the windows, says Mazan. If necessary, put in more doors and windows. If that leads to a direct draft or rain coming in the stall, extend the roof over the window or set up a windbreak outside. Then look for fungus. Clean everything thoroughly with dilute bleach (one part bleach to nine parts water). Make a note of where dampness accumulates, and remember to check back for further growth.

In order for the ventilation "stack effect" to function properly with cool air coming in low and hot air rising out the top of the structure, barns should have inlets (vents) placed under the eaves, with outlets higher up in the roof (a cupola, or series of cupolas, along the roofline is one popular arrangement). Just how big these vents should be, and how far apart they should be spaced, depends on how large the barn is, its location, the local climate, and a number of other factors. (Remember that young foals are much more vulnerable to chilling from cold drafts than older horses. That means foaling stalls should be in the center of the barn, well away from doors.)

If you must store hay overhead, spread a tarp on the floor to seal the partition between the hay and the horses. Finally, if horses are kept in interior stalls with no windows, be sure that these horses get the maximum turnout.

When redesigning your older barn for the benefit of your horse, consider how horses were designed. According to Mazan, "Horses were meant to walk and eat roughage 20 hours out of the day. The closer we can keep them to living that way, the fewer problems we are going to have with them."

About the Author

Katherine Walcott

Katherine Walcott is a freelance writer living in the countryside near Birmingham, Al. She writes for anyone she can talk into paying her and rides whatever disciplines she can talk her horses into doing.

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