Build a bird cage by constructing a frame from untreated wood and enclosing the frame with stainless steel mesh. Alternatively, convert a piece of furniture, such as a wardrobe or hutch, into a bird cage or aviary by removing the sides and attaching stainless steel mesh to the frame.
Begin by determining the size, number and species of birds to house in the cage. Design a cage long and wide enough for the birds to move about freely, stretch their wings comfortably and play. Soft-billed birds, such as finches, need space to fly. Select stainless steel mesh with hole dimensions small enough that birds cannot escape or push their heads through it.
While galvanized mesh, often called hardware cloth, is cheaper the stainless steel mesh, the zinc present in the material is toxic to birds. Plastic-coated wire is also unacceptable, as birds may chew through the plastic coating and expose toxic zinc underneath. Choose only untreated lumber to construct the cage frame. Birds enjoy chewing on wood, and treated lumber contains toxins unsafe for consumption.
After constructing the frame, attach the stainless steel mesh using steel staples. When housing parrots, place the staples on the outside of the frame, out of the birds' reach. Parrots can easily remove staples with their beaks. Make a door large enough to accommodate the birds and the removal of any large cage accessories, such as perches or nest boxes. Small doors near the feeding dishes allow feeding and watering without letting the birds out.
To facilitate easy cleanup, use large metal baking pans to line the bottom of the cage. A layer of mesh above the pans prevents the birds from landing in their waste.