You can build a small aviary with PVC pipe for your bird. This project is simple but sophisticated and will save you money by giving you more space for your dollar. You can upscale this project to accommodate a larger number of birds. The parts for this are money saving compared to buying most commercial aviaries.
Gather all of the parts that you need. Cut the pipes into nine 6-foot lengths using a hacksaw if this is not done for you already. Dry fit all the pipes together.
Make the base of the aviary. Lay four of the 6-foot lengths in a square. Slip a slip T connector onto two pipes that are opposite each other and position them in the centre of these two pipes. Use the three way 90-degree elbow connectors at each of the corners with the empty hole pointing up and the other two holes connecting to the two adjacent pipes.
Build the walls. Slip a 6-foot length of pipe into each of the holes at the corners that points up. Slip another 6-foot length into each of the slip T connectors that are on the base.
Make the spine of the roof from another 6-foot section of pipe. Put a slip cross fitting in the middle of this pipe. Slip the ends into a the remaining two slip T fittings in the base of the T.
Hook the walls together with the tops of the pipes going into the spine. Bend the walls in from the sides to the connections on the spine. Start by connecting the two pipes that are midway in the walls coming up from the slip T connectors in the base to the slip cross fitting in the middle of the spine.
Seal the pipes together. You have to sand the pipe ends so that there are no burrs. Coat the inside of the pipe fittings and the parts of the pipe that will need to be permanently together with PVC primer and then with PVC cement. Slide the pipes together where you want them while they are wet. Wipe off the excess primer and cement with a rag.
Drape the wire mesh over the frame and cut it so it covers the frame. Bend the sharp edges of the wire outward to protect the birds and use zip ties every inch to seal the seams between the mesh panels. Use more zip ties to hold the mesh to the frame at 3-inch intervals (unless there is an open gap where you return to 1-inch spacing). Remember to leave half of the panel at the end open so that you can use it as a door. The aviary should look like a half of a pipe with the open side on the ground and should have half-moon shaped ends.
Make the door by cutting the half-moon shaped panel's wire down from the peak of the roof (at the spine) straight down to the ground and from the top of this line around, next to the frame to remove half of the half-moon shape.
Reinforce the door with more PVC pipe so that the birds do not escape. Cut the PVC pipe to fit the edges of the new door opening as it goes along the frame. Use three 90-degree elbow connectors, sandpaper (for burrs), primer and cement to form the door out of two 5-foot-10-inch PVC pipes and one 2-foot-11-inch pipe at the base. Attach the frame of the door with more zip ties. Use loose zip ties every inch to make a hinge down the line that drops from the peak so that it is tight enough that birds will not escape.
Bend every remaining loose end out on the cage to prevent injury to the birds inside the cage. Make sure that the door closes tightly enough to prevent the birds escaping, and use rope and tent stakes to keep the aviary on the ground.
Select wire mesh that is small enough that your birds won't get caught in it, strong enough that the birds won't get through and smooth enough that the bird(s) won't get cut. These requirements will vary depending on the bird Chicken wire is fine to use for some birds (including chickens) but may be too flimsy for a bird with a powerful beak or that likes to pull at the edges of the cage. Make sure that you don't forget to use the zip ties on the wire where it meets the base and that the ground around the cage does not have any gaps. Add perches and nesting boxes along with other essentials to the cage for your birds.
Wire and tools can cut or scratch you. Wear goggles and gloves when doing this project. Do not lean your body against the wire and wear sleeves that are protective so that when they get snagged, you don't get hurt. Use the tin snips and pliers to handle the wire when bending/shaping the wire. Cover sharp edges on the mesh cage with brightly coloured liquid electrical tape in a strategic way so that the birds can't reach it (since it is a hazard to them). Use the PVC primer and cement in a well ventilated place. Read all labels and follow the instructions and safety precautions. be careful around sharp tools.