You don't have to raise chickens long before you'll come across something that reads, "chicken coops should be dry and draft-free, but well-ventilated". That's excellent advice to be sure, but what exactly does that mean? What's the difference between a draft and ventilation?
Drafts vs. Ventilation
So to begin with, a draft is defined as "a current of air being drawn into a room". Ventilation is defined as "the process by which outdoor air is intentionally introduced into a space and stale air is removed". Not much help there....
But in layman's terms, a draft has come to mean openings, cracks or crevices down near the floor of the coop, while ventilation refers to openings (generally windows and vents up under the eaves) higher up. Preferably above the level of the chickens' heads when they are asleep on the roosting bars.
So why is this important?
Why Ventilation is Important
Well, the most important reason to have good ventilation in your chicken coop is to allow the ammonia fumes created when the chickens poop to escape. Ammonia fumes are lighter than air, so ventilation up high will allow them to rise and drift out of the coop.
Ammonia fumes are extremely corrosive. The build up of ammonia will cause eye irritation burning of the nose, throat and respiratory tract. This is especially damaging to poultry because of their sensitive respiratory systems. Continued exposure to the fumes can result in acute respiratory distress and even blindness.
Ammonia fumes are extremely corrosive. The build up of ammonia will cause eye irritation burning of the nose, throat and respiratory tract. This is especially damaging to poultry because of their sensitive respiratory systems. Continued exposure to the fumes can result in acute respiratory distress and even blindness.
The fact that that chickens are small and close to ground level, where high concentrations of ammonia fumes are initially located, means that allowing the ammonia to escape as quickly as possible is critical. Vents located under the eaves of your coop providing a cross breeze will be effective at allowing the fumes to escape.
But there's also another reason for good ventilation.
Although ammonia fumes are lighter than air and will naturally rise, in high humidity or moist locations, the resulting ammonia vapors are actually heavier than the air and will settle on the ground instead of rising. Clearly, this poses a risk to your flock.
Providing good ventilation in your coop will also allow any moisture in the coop to escape. Some moisture is normal especially if you raise ducks. They tend to emit a fair amount of moisture into the air as they breathe, so if you raise ducks either alone or with chickens, proper ventilation becomes even more crucial. (Side note: I never recommend leaving water inside your coop for the simple reason that it introduces potentially harmful moisture to the coop.)
Most chicken coops have windows that can be open or shut, depending on the time of year, climate and temperature. There should also be small openings or vents up high that stay open year round to provide good airflow and an escape route for ammonia and moisture. Remember to cover all windows, vents and other openings with 1/4-1/2" welded wire for predator protection.
Reducing Drafts
Because it's important not to have cold air blowing on your chickens when they're sleeping, any openings at roost level or below should be closed up in the winter. That will reduce the drafts in your coop.
Obviously, there's not a lot to be done about the small "pop" door in the coop. That needs to be left open during the day to allow your chickens to come and go to lay their eggs, but in the middle of the winter, it allows a good amount of cold air into the coop.
On super cold blustery days, the chickens spend a good portion of the day inside the coop out of the wind and snow, putting them right in the path of the rush of cold air coming in through that small opening.
My solution is to install "draft drapes" across it. Once the chickens get used to walking through them tied back at each side, I gradually can leave them hanging down over the opening during the day to keep the winter air out.
My solution is to install "draft drapes" across it. Once the chickens get used to walking through them tied back at each side, I gradually can leave them hanging down over the opening during the day to keep the winter air out.
More details and how-to of this cute and practical project can be found in my new book 101 Chicken Keeping Hacks, and I can tell you that this being my second winter using them, they do make a big difference in helping to keep my girls' coop warm and draft-free all winter long!
