Every year, as the weather turns cold, my husband starts closing down the windows of the chicken coop. He means well, but every year I explain why it’s very important to keep the chicken coop well ventilated, and why it’s even more important in cold weather. Notice the windows of the coop in the photos are wide open – front and back.
An extremely important element of successful chicken keeping is assuring that there is adequate ventilation in the chicken coop. Failing to plan for or provide sufficient airflow is a frequent mistake that poultry keepers make. And, it can quickly lead to sick birds.
Chickens generate a lot of moisture, ammonia, and heat – so it’s absolutely critical to ventilate well to remove the excess from the coop. The more time your chickens spend indoors, the more important it is to supply good ventilation.
Beginning chicken keepers often believe that coops should be airtight and insulated, but nothing could be further from the truth. Providing plenty of ventilation keeps chickens healthy by reducing harmful ammonia fumes, removing excess moisture, supplying oxygen-rich air, reducing airborne disease organisms, removing irritating dust, and reducing heat in the coop.
Why Coops Need Ventilation
1. ELIMINATE HARMFUL AMMONIA FUMES
A great deal of ammonia is released into the chicken coop from the chicken’s droppings. Ammonia fumes can cause your flock everything from irritated eyes and sinuses to respiratory distress, overall poor health or even death in extreme cases. Placing ventilation up high in your coop, well above the level of your roosts, ensures that the ammonia fumes created by the chicken manure in your coop will escape and not be trapped inside.
An easy way to check whether your coop ventilation is adequately removing ammonia fumes is to check for ammonia smell, if you can detect ammonia near the coop floor (at approximately the same height as the chickens), then the coop airflow needs to be increased.
2. REMOVE MOISTURE FROM THE COOP
Chickens don’t sweat, but they do generate a tremendous amount of water vapor. They generate it both by breathing and from their droppings, and all that water vapor causes chicken coops to be humid. High humidity makes chickens more susceptible to respiratory illness and frostbite.
Good ventilation removes this dampness and humidity from the coop, reduces respiratory problems, and chickens can withstand surprisingly cold temperatures if the coop air is dry. Chickens are naturally cold hardy but their legs, combs, and wattles are not protected with feathers and are susceptible to frostbite.
Frostbite occurs in the presence of sub-freezing temperatures and moisture. This moisture settles on the chicken’s vulnerable combs, wattles, and toes and is the perfect condition for frostbite to occur. Keeping the coop dry and well ventilated will solve the problem of frostbite.
3. PROVIDE OXYGEN-RICH FRESH AIR
Chickens deplete oxygen in the coop quickly because they have such a high respiratory rate, and also produce large quantities of carbon dioxide. In order to get the oxygen they need to survive, the carbon dioxide-laden air must frequently be replaced by fresh oxygen-rich air.
4. REDUCE AIRBORNE DISEASE ORGANISMS
Because of their high respiratory rate, chickens are also quite susceptible to airborne diseases. Although they can’t be seen, airborne disease organisms buildup quickly in stagnant air inside a chicken coop and can cause an entire flock to become ill. Again, it’s critical that airborne disease organisms be minimized by moving them out of the coop with fresh air.
5. REMOVE RESPIRATORY IRRITATING DUST
Chickens are well known for producing lots of dust, and all that dust in the confined space of a coop fills the air with dust particles. Because of their high respiratory rate and sensitive respiratory systems, all those dust particles need to be regularly removed from the coop to keep the flock healthy.
6. REDUCE HEAT RELEASED DURING BREATHING
Since chickens don’t sweat, they release their heat by breathing and are constantly adding heat to the coop. Chickens are better equipped to handle cold weather than hot weather and do best at temperatures below 75°F. They really begin to suffer at temperatures above 90°F and can die, so ventilation is needed to keep the coop cool, particularly during warm summer weather.
When To Keep Coops Ventilated
The amount and location of ventilation needed in a chicken coop vary according to the season and the weather conditions during each season. But, chickens produce water vapor, ammonia, carbon dioxide, and heat continuously; while dust and airborne disease organisms are always accumulating, so chicken coops need to be ventilated at all times. Some think that chicken coops should be closed up during cold weather to keep the birds warm, but that’s not true. They need ventilation all year long.
But ventilation is different than a draft. A draft is air blowing directly onto the chickens while they roost and should be avoided. Ventilation is airflow rising naturally from a lower position to an exhaust opening or ridge. Ventilation will naturally carry away the heat and harmful substances that can lead to problems in your chickens.
In cold weather, make sure that the ventilation isn’t causing drafts. Cold weather ventilation should be high up and protected from rain or snow by roof overhangs. You don’t want a cold draft wafting across your chicken roost(s) at night. In warm weather, vents that provide a breeze are good so openings lower in the coop are desirable.
How Much To Ventilate
The general rule of thumb is to have 1/5th of your coop walls be windows or vents. The lower windows can be left open in the summer and then closed in the colder months, leaving only vents up high open. If the climate is very wet or the coop is crowded, then more than the recommended amount of ventilation will be needed.
A fan may be necessary, particularly in warmer climates, to provide an adequate flow of fresh air. A fan that can supply 5 cubic feet per minute, per chicken in the coop will usually provide adequate ventilation.
There are many manufactured chicken coops available for purchase, but that doesn’t mean they have sufficient ventilation. It may be necessary to add additional openings for your conditions.
When adding ventilation openings, be sure to cover them adequately with hardware cloth (a welded wire product). This will keep predators from gaining access through any openings in the coop. It comes in quarter-inch and half-inch varieties that are adequate for keeping out rodents and larger predators.
Obviously, the amount and location of ventilation needed changes as weather conditions change. So, it’s important to have many ventilation options that can be opened or closed as necessary. Consider your coop ventilation requirements carefully, and plan for more, not less. And, don’t shut off all the ventilation in winter – chickens need it then too! Check out other important chicken coop design features in 10 Important Chicken Coop Design Features.