The project of coop-building can get very complicated if you let it. But it needn't be – building a chicken coop is relatively easy for creatures that are not at all pernickety about their home.
The first thing you need to do is decide what function your coop is going to have. Some chicken keepers use the coop only for roosting (where the chickens sleep at night). This means it can be relatively small and simple. Others use the coop for shelter and nesting/laying area throughout the day and night. A coop can have an attached, fenced-in yard or be free-standing.
So before you begin, take a good look at your property and think about what you want to accomplish with your chicken-keeping efforts. Consider the proximity of your neighbors, the type and number of predators (when you begin keeping chickens, you will find predators you never even knew existed), how many chickens you want to keep, and how much space you have available. This is not a detailed guide by any means, but here are some easy steps you can take to make your own chicken coop.
1. Start with a supporting structure. A dog kennel or crate is ideal. It will have a ready-made door, and its wire sides allow you to mount perches easily and plan for air circulation.
2. If you are using the dog crate method, you will need to cover the crate with solid wood sides. Use pieces of plywood that are slightly larger than the crate's sides by about 2 inches.
3. To make a solid door from the wire dog crate door, you will need to drill holes in the plywood and mount it to the door using wire. Cut out a space for the sliding lock. You will also want to get some sort of padlock or clamp to secure the slide lock – predators like raccoons can quickly learn to open an unsecured slide lock.
4. If you are not using the dog crate, you will need to build a supporting structure. This is best accomplished by making a frame out of 2x4s or 2x2s. Begin by laying out a square or rectangle on the ground using 2x4s; attach them at the corners. Then you can decide if you want to build an A-frame type of coop or a square one. Build the frame upward, attaching vertical pieces to each corner and in the middle of three of the sides. Slant these vertical pieces if you are doing an A-frame. Leave one side open so you can construct a door. Then cover this frame with a combination of plywood or hardware cloth/chicken wire.
5. Insulation is something you might want to consider if you live in a very cold climate. If you insulate, you will need to make double walls with the insulation between them.
6. The kind of door you make is important. It can be any size or shape you choose as long as the chickens can get in and out easily during the day and it can be locked securely at dark. Consider building a door that locks at the top and has hinges at the bottom so it can double as a ramp when open.
7. The roof is also important. If you are using the dog crate structure, your roof will be flat. A-frames, of course, have sloped roofs. Either way, an inexpensive way to make the roof water-resistant is to cover it with plywood followed by roofing tiles.