A chick pen is the in-between home for birds that have outgrown the brooder but are still too small to live with your hens. Most people plan the brooder and the coop and forget this part.
Then week five shows up, the tote smells like a barn, and you’ve got six half-feathered birds with nowhere to go.
I keep twelve hens and one bad-tempered rooster, and every batch of chicks I’ve raised spent longer in this middle stage than I planned. So here are four chick pens that work, how big each one has to be, and what it takes to keep a predator out of it. The grown flock’s run is a different job, and I covered it in my chicken pen ideas for adult hens.
The Middle Stage Lasts Months, Not Days
Chicks usually leave the brooder somewhere around five or six weeks, once they’re mostly feathered and the heat can come down. The signs to look for are in the post on when chicks can go outside. What people miss is the other end of the stage.
Young birds are safest joining grown hens once they’re about the same size, and for a lot of flocks that means keeping them apart until around 18 weeks.
A chick that leaves your brooder at six weeks can live in its pen for three months, through rain, a cold snap or two, and whatever comes sniffing around the yard at night.
Three months is a long time.
That’s why I build a chick pen like a small coop (a roof, a floor I trust, a door that locks) instead of a box I’ll toss in a week.
Honestly, the pen is where I’d have lost the most birds if I’d cut corners. Half-grown chicks are too big to hide under a heat lamp and too small to fight off anything.
Size the Pen for the Bird It Will Become
Space has to grow with them. A good rule is 1 square foot per bird from 5 to 8 weeks, then 1.5 square feet from 8 weeks on, and more again for big breeds. And only the covered indoor floor counts toward that number. The open run is a bonus.
For six chicks, you need 6 square feet of shelter at five weeks and 9 square feet by eight weeks. A 3-by-3 box covers week eight and falls short right after. I’d start at 4 by 4, which leaves room to spare.
Feeder room grows too: 2 inches of feeder per bird at 5 to 8 weeks and 3 inches after that, so six birds need 18 inches of feeder by eight weeks, which is a lot more than any little chick feeder has.
That’s why there’s always one chick standing at the back, yelling.
Chick Pen Idea 1: A Wire Corner Inside the Coop
If your coop has spare floor, this is the cheapest pen there is. Frame off a corner with 2×2 lumber, wrap it in half-inch hardware cloth, and hang a small door you can latch. The chicks get the coop’s roof and walls, plus its locked door at night.
The hens get to stare at them through the wire every day, which is the whole point.
The catch is floor space. Every square foot you fence off is one your grown birds lose, and a crowded coop gets wet bedding fast. I’d only do this in a coop that’s already roomy for the flock it has.
Put a low perch in their corner, a scrap of 2×4 a few inches off the floor. They’ll start roosting sooner than you’d think (mine were hopping up at six weeks), and a perch they can reach keeps them from trying the hens’ roost too early.
Chick Pen Idea 2: A Grow-Out Pen Against the Run Fence
This is the one I like best.
Build a small pen that shares one wall with the hens’ run. The two groups see each other and squabble through the wire for a while, which beats squabbling for real later.
Putting new birds in side-by-side runs for a week before they share space is a well-worn way to find the worst personality clashes early. With a shared wall you get that for free, for months, without lifting a finger.
The grow-out pen needs its own shelter, though. A plywood box with a slanted roof, a solid floor and a vent high on the side away from the wind is plenty. Set it on blocks so the floor stays dry, and give it a door you can close at dusk.
Chick Pen Idea 3: A Dog Kennel or Playpen in the Garage
For an early spring hatch, a garage pen saves you a lot of worry. A wire dog kennel or a puppy playpen with cardboard on the floor and pine shavings on top works fine for a few weeks. A 48-by-30-inch kennel has 10 square feet of floor, which covers six birds at the 1.5 square feet they need from eight weeks.
Two rules here. Keep any heat lamp at least 20 inches from anything that burns, and hang it from a chain instead of trusting the clamp it came with. And put a lid on top, because a seven-week-old chick can flap onto the edge of a playpen and then onto your car.
The garage is a waiting room, not a home. It’s dusty and dark, and it teaches them nothing about weather. Once your nights are mild, move them out to one of the other pens.
Chick Pen Idea 4: A Chick Tractor on the Lawn
A chick tractor is a small pen with no floor that you drag to fresh grass every day or two. The chicks scratch and chase bugs, and their droppings get spread thin instead of piling up in one corner.
Build it light enough to move by yourself and heavy enough that a dog can’t tip it. One end needs solid walls and a roof, so there’s shade and a dry spot when it rains.
Since it has no floor, anything that digs can get under the edge, and a bumpy lawn leaves gaps all by itself. So a tractor is a daytime pen for me. At night your birds should roost inside a secured spot with every door locked, which means carrying them back to a shelter at dusk or parking the tractor tight against one.
Wire and Floor: What Keeps Predators Out
Half-grown chicks are in the worst spot. When chicks go missing and nothing else looks disturbed, the usual suspects are a snake, a rat, a raccoon or a house cat. Hawks hunt by day and can carry a young bird off whole, which is why every pen above has a roof.
Raccoons are the predator I take personally. They’ll reach through wire and pull a bird’s head through it, so chicken wire only keeps chickens in.
Use half-inch hardware cloth on the walls of any pen that holds birds at night. For the floor, either build a solid one or bury hardware cloth at least 12 inches deep around the edge, so a digger hits wire instead of dirt.
I lost birds to a raccoon once, through a latch I trusted.
Now every pen door gets a latch that takes two moves to open, like a spring hook through a hasp. Kinda paranoid, sure, but I haven’t lost a bird since.
Heat at Night in a Chick Pen
Chicks in a pen need a lot less heat, but not zero. Keep supplemental heat going until they’re well feathered, because taking it away too early makes breathing problems more likely. The target at five to eight weeks is 70 to 80°F, and the night to fear is a cold one in the first six weeks.
Your chicks will tell you more than a thermometer.
If they pile up under the heat, they’re cold. If they’re spread out at the far edges with their beaks open, they’re too warm.
For an outdoor pen I’d pick a heat plate over a lamp at this age. There’s no bulb to break and nothing glowing a few inches from dry bedding. I learned to respect a heat lamp in a wooden box the way you respect a space heater by the curtains.
Taking the Chick Pen Down
You’re done with the chick pen when the young birds are about the size of your hens, not when you’re tired of it. Before you open the gate, give both groups a week where they can see each other all day. The shared-fence pen does this already, which is one more reason I like it.
When they do mix, put out extra feeders and waterers so the new birds can eat without walking past the boss hen. My whole process, with what counts as normal pecking and what counts as an attack, is in the post on integrating chicks into your flock.
Leave the pen standing for a week after. If one bird gets picked on hard, you’ve got somewhere to put her back.
The Chick Pen I’d Build for Six Birds
If I were starting today with six chicks and a run that’s already predator-proof, I’d build the grow-out pen against the run fence. Here’s the shape of it:
- A 4-by-8-foot pen sharing one long side with the run, framed in 2x4s, with walls and roof in half-inch hardware cloth.
- A 4-by-4-foot plywood shelter at one end, on blocks, with a solid floor, pine shavings and a door that locks at night.
- That shelter is 16 square feet for six birds, well over the 9 they need at eight weeks.
- A hanging feeder with at least 18 inches of eating room, and a second waterer for hot days.
- A heat plate in the shelter until the last pin feathers open up.
It’s a weekend of work. Kinda funny, but the lumber and the wire cost more than the chicks did. It holds every batch after this one, though, and your hens get used to new faces on the other side of the fence.
If you’re still using a tote right now, you’ve got time, but not a lot. Build the pen before week five.
Nobody does good carpentry with six chicks yelling in a tote in the living room.
