They call it chicken math. It’s basically the justification chicken lovers use when they buy more chicks. How many straight run chicks should you buy if you want eight laying hens? How much room do you need? Two square feet of space per chicken if the coop is only used for sleeping, 4 square feet per chicken for the entire living space. Or is it 10 square feet of run, 4 feet of sleeping space? When you begin to consider adding more poultry, the natural next step is learning how to build a chicken coop for your expanded flock.
It’s the phenomenon that happens to someone who wants “three laying hens, just for a few eggs” and ends up with 35 backyard chickens.
I started with five chicks, which turned into four laying hens and one rooster dinner. Then I found an online chicken forum. Havoc broke loose. As I got to know other members of the forum, I realized four chickens were just not enough. I mean, I have four members of my family. Really, I do need more chickens if I’m going to feed everyone, especially if one goes broody, right?
But as the chicken math turned to multiplication, I knew I couldn’t humanely keep the number I wanted if I just had my little coop. I needed to figure out how to build a chicken coop that could house more than six hens.
I had built the coop for my five chicks, using an empty area beside the garden shed. Really, I could fit six hens in there… more if I let them run around the garden all day. But I wanted more than six hens. Oh yes, I did. I wanted Rhode Island red chickens, australorp chickens and cream Brabanters, and exchequer leghorns. Plus, I didn’t want my garden to get eaten.
I knew exactly where to put this coop. Just that past summer, my landlady gave me permission to fill in one of the koi ponds. Now she suggested I use the area for the new coop. I had three criteria for the coop: First, it needed to house at least 20 chickens at night. Second, it needed to be affordable. Third, it needed to be portable, or at least be able to disassemble if we rented a new house or the neighbors rioted against urban farming.
One friend had used a Rubbermaid shed that she had purchased secondhand on Craigslist. I would have loved to find that deal again, but nobody was offering. If I wanted a pre-fabricated shed that was large enough, that had adequate ventilation and secure doors, I would be spending about $1,000.
Another friend built her chicken coop from scratch. It was solid construction, just small enough that it didn’t need a building permit. It was also expensive.
So I told friends that I sought surplus building materials for a coop. It didn’t take long. One friend had an old bedroom set. Another had just renovated his house and had some sheets of OSB left. Another had a habit of frequenting auctions and buying old industrial racks. (His long-suffering wife is one of my heroes.)
Here’s what I had donated or on hand to build my coop:
- Bedroom set: a set of shelves, headboard/footboard and running boards of a twin bed.
- Part of an old bunk bed, including the ladder, railings, and running boards.
- Four sheets of OSB, 4’x8’
- One sheet of plywood, 4’x8’
- Four industrial shelving units
- An old door, the very cheap kind. But it had a doorknob.
- Leftover pieces of laminate material for countertops
- Two 2x4x8 boards
- Paint from my art projects
Here’s what I bought new:
- Four more 2x4x8 boards
- 25’ roll of hardware cloth
- Pint of polyurethane varnish
- 4 cans of spray paint
- A can of oil-based primer
- Bolts, washers, nuts, a drill bit, screws, and nails
- Latches, hinges, and handles
By the end of the project, after all the gas for hardware store runs, we ended up spending about $200 on the chicken coop.
The taller of the industrial racks measured 4’x8’. Since our two worst enemies in Reno are wind and raccoons, the coop had to be planted firmly in the ground. By turning these racks upside down, we had 6 inches of base to bury. This also gave us a flat surface with holes in it to bolt the roof onto. (The feet of the racks.) After burying the racks, we set the sheet of plywood on top of these feet and bolted them down.
The old bedroom shelf became the nesting box, and a rather sturdy one at that. We already had three nests on the bottom, made up of the shelves. Russ cut out one side, to allow entrance from inside the coop. I cut pieces of laminate to divide this top portion into separate nests. We bolted the nesting box securely to the metal frame.
The headboard/footboards of the twin bed made perfect windows for ventilation. Just add hardware cloth! We bolted running boards to the metal frame, them bolted the footboards to the running boards. Laminate pieces filled in the bottom space perfectly. We bolted the door onto the other running boards.
The other set of industrial shelves became the mini-run. We assembled these into a 3’x3’ block, and bolted this to the original metal frame. Now came time to fill in the spaces. We cut the OSB to fit and bolted that to the framework. We covered the windows with hardware cloth, securing it tightly to the wood. The 2×4 boards serve as perches for the chickens and to fill in areas where my upcycled building materials didn’t quite fit right. The old railings and the ladder from the bunk bed also provided perches.
Now it was functional, but very, very ugly. My landlady showed great charity and understanding for even allowing us to keep chickens. I had to keep this coop from becoming an eyesore. Good thing I know how to paint. Since we built this mid-February, I only had daylight until about 5pm. After sundown, I took two pieces of laminate inside to paint the nesting box doors. This is where my artistic side comes in.
And here it is! In the winter, I cover the mini-run with plastic, turning it into an air-warming chamber. The air comes into the run through the pop door, where strategically placed pieces of laminate act as a windbreak. The 6mil plastic warms the air, which is then pulled into the coop. Humidity leaves through open vents in the top.
So far, the coop has withstood wind, snow and rain, raccoons, and children. We’ve had to replace a few latches, mostly due to children, but so far nothing has gotten into the coop that wasn’t supposed to. And the really good news: Since I use my entire backyard as the chicken run, this coop is only for sleeping and nesting. Which means I can have about 30 chickens and 5 ducks comfortably in the coop. Now that’s chicken math!
Remember, there’s an art form to introducing chickens and chicks to your existing flock, so once you’ve expanded your coop and run, make sure to do your homework.
Originally published in 2013