There is no magic number for how much space chickens need. We keep them in so many different conditions, with all kinds of flock make-ups, use different management techniques, have different climates, flocks have different dynamics, individuals have different personalities, in suburbia or rural, and all that, how could one magic number cover everybody?
Coop space by itself isn’t all that important either. It’s how much total space is available when they are awake. It does not matter if that is in the coop, coop and run, or if they roost in trees and totally free range. The key is that it has to be available every day of the year. Obviously climate or your management practices will have a big influence on that.
I understand that people with no experience need to know where to start. That’s why we have guidelines. Guidelines are not absolute laws of nature. Following them does not give you a guarantee that you will never have a problem. Violating them does not guarantee that you will have a total disaster. The guidelines will keep most people out of trouble most of the time. For some of us, they are overkill. We don’t need that much. For some people, they are not quite enough. We all have our own unique situations.
Commercial operations have proven that you can get by with only 2 square feet per bird. But they have to follow specific management techniques to make that work. For example, they automatically trim the beaks so they can’t eat each other. They have serious poop management issues. They tightly control food and lighting. Most of us are just not going to learn how to do that and work that hard, plus we don’t want to treat our chickens like that.
I’m a huge proponent of providing as much space as I can. I find the more space I give them the fewer behavioral problems I have, the less hard I have to work, and the more flexibility I have if something happens.
Your question is “What problems might arise?” Realize that these things “might” arise. There is a difference in what might possibly happen and what will absolutely without a shadow of a doubt each and every time happen.
As far as behavioral, if they are crowded, it could range anywhere from feather picking to fighting to cannibalism. Some chickens handle confinement much better than others. There are breed tendencies but there can be a lot of difference between individual chickens in the same breed.
Chickens have developed ways to live together peacefully in the flock. One of the ways they have developed is that in case of a conflict the weaker runs away from the stronger or just avoids them to start with. So they need room to run away or avoid. How important that is depends on the flock dynamics. Chickens in a flock will develop a pecking order. They start on that as soon as they hatch if they are raised together but the pecking order can change as they mature. How that normally gets sorted out is that when a chicken invades the private space of another and the pecking order is not sorted, one chicken pecks the other or somehow tries to intimidate it. If one runs away, the issue is sorted. If one does not run away, they fight. This may be a very brief skirmish that quickly evolves into running and chasing or it can get really serious. If there is not enough room for them to run away the odds of violence goes up.
For working hard, think poop management as an example. Chickens poop a lot. If poop gets wet or really builds up, it can stink. In a rural area well away from people that may not be as big a deal as with someone in suburbia. But a wet stinky run is also unhealthy so even in rural areas there are serious reasons to not let the poop build up too much. The more spread out they are, the less it builds up. They will poop a lot on the roost so even in big coops it’s often a good idea to make special arrangements to manage that poop.
If you feed and water in your coop, you need enough room so they don’t poop in the feed or water while on the roosts.
For flexibility, if you restrict your space so you have to follow specific management techniques, you have a lot of trouble responding to problems. Let’s assume you rely on them having access to the coop and run both when they are awake and a tree limb falls on the run so you have to fix it. Or say a predator finds a way to get in your run. If your coop is big enough you can leave them locked in the coop until you get home from work to fix it. Otherwise you have to take care of it then. If you ever want to add chickens to your flock, integration goes a lot easier if they have room to run away or avoid while they are sorting out the new pecking order. If you ever want a broody hen to raise chicks with the flock, that goes a whole lot easier if Mama has enough room to work with, plus the chicks need room after they are weaned so they can run away and avoid while they are growing enough to make their way in the pecking order.
When I am gone for a few days, I get a neighboring college student to take care of the chickens. She’s been doing this for several years. With my large coop, it doesn’t matter if she waits until fairly late in the morning to let them out of the coop. If my chickens were shoe-horned in a tiny space, that could be a real problem. When she graduates or moves out of her home, we’ll have to find someone else to take care of them. That’s going to be a lot easier if they are not tied to a real tight schedule.
I’ve tried to give some examples of what problems “might” arise. I can’t give you any guarantees that any of these will or won’t come up. As tight as you have them, your risks of having problems are a lot higher than mine, but that does not mean you will have any of these. I wish you luck!
