A birdhouse should be built with a specific kind of bird in mind. While there are those that can live in almost any kind of enclosed shelter, most birds will prefer houses that resemble their natural nesting places in cavity size. Majority of the birds will occupy houses of only one compartment with a single entrance, but there are species that are known to live in colonies in apartment houses with 10 to 30 compartments. Others will not nest in enclosed birdhouses.

The design is basically a matter of personal sense of aesthetics. Birds are more concerned about their safety and comfort. Therefore, the right dimensions should be considered in providing a birdhouse. The box height, depth and floor, diameter of entrance hole and height of hole above the box floor are all important aspects for nesting birds. Other considerations would include ventilation, drainage, accessibility, limiting predator access and ease of maintenance.

The usual birdhouses are the closed type. A simple construction would consist of walls on all sides, a roof and a circular entrance that is large enough only to allow the desired bird to enter. The entrance is placed well above the middle of the compartment to protect the nestling from the weather and from predators. The roof of the birdhouse should be slanted to allow rainwater to drain and one or more small holes under the eaves to provide ventilation as well as a small hole in the floor to permit drainage. A wooden perch placed beneath the entrance is not recommended since it may be used by predators to get to the birds.

A birdhouse without ventilation is like an oven that will suffocate the birds. Water that sits at the bottom of a birdhouse due to non-existent drainage invites parasites and diseases to attack. Entrance holes that are too big provide access to undesired animals like squirrels, mice or snakes. Predator guards are a necessary feature.

Most birdhouses can be opened from the top, front, side or bottom but boxes that open from the top and front provide the easiest access. Top opening is less likely to disturb nesting birds while side and front opening boxes are convenient for cleaning and monitoring. Bottom opening is likely to result to the nest falling out. Most cavity nesters such as the Eastern Bluebird, House Wren or Chickadee can comfortably nest in a birdhouse built for a single nest. Purple Martins are very comfortable with nesting boxes built for multiple birds.

There are some bird species that will not use enclosed birdhouses such as the Barn Swallow, Eastern Phoebe and Mourning Dove. They can be attracted through the use of nesting shelves which has a roof, back, bottom and narrow side walls with an open front. These shelves should be placed under overhangs and eaves. The species that it attracts are the so-called open nesters that build their nest on open branches of trees or shrubs.

Other bird species are classified as platform nesters. Platforms are open on all four sides and are usually placed in shrubs. Bird species such as Catbirds prefer to nest in platforms mounted near the ground, on walls behind shrubbery or under eaves and on fence lines covered with vines. There are also gazebo types mounted in bushes. Since platforms are open on all four sides, the corner posts must be able to support the roof. This is a good alternative for other birds that prefer to have their nest in a somewhat similar environment when natural nesting sites are not available.