I believe there are a few designs for bluebird houses.
https://www.thespruce.com/free-bluebird-house-plans-385671
Bluebirds are some of the most desirable
cavity-nesting backyard birds, but they need a safe, attractive place to nest. These free bluebird house plans can help any birder build just the right size, shape, and style of house to appeal to bluebirds and attract nesting bluebird pairs.
Choosing a Bluebird House to Build
Bluebirds will not nest in just any
birdhouse. The right birdhouse will not only provide good, safe shelter for a brooding adult and its nestlings, but it should also be the proper size to admit bluebirds without encouraging unwanted residents.
The best dimensions for bluebird houses are:
- Entrance hole: 1.5 inches (1.56 inches for mountain bluebirds)
- Entrance height: 6 inches to 10 inches above the house floor
- Interior floor space: 5 inches by 5 inches to accommodate broods of five to eight chicks
- Total height: 8 inches to 12 inches with the back slightly higher to shed water
Different design options are serviceable for bluebirds, including rectangular houses, sloped patterns, round cavities, and houses with either front or side panels that open for easy monitoring. Any of these houses are ideal for nesting bluebirds, so long as the house is constructed with their needs in mind and positioned to keep them
safe from predators.
ND1939 / Getty Images
Free Bluebird House Plans
Several websites offer different bluebird house plans for free printing or downloading, including:
In addition to these websites, many local bluebird societies or conservation groups may have suitable plans available. Similarly, most birders who maintain bluebird houses or work on a bluebird trail would be happy to share their experience to help more birders get involved as bluebird landlords.
Other Considerations When Building a Bluebird House
When using free plans to build a bluebird house, it is important to create the
best possible home for resident bluebirds. To do so, don't forget:
- Safety features: A safe birdhouse needs proper ventilation to keep birds cool, as well as a predator guard to minimize the risk from raccoons, cats, snakes, and other animals that will prey on vulnerable bluebirds. Avoid house plans that feature perches, which bluebirds do not need but which will give a convenient handhold to predators.1
- Monitoring: Because so many insects, mice, and other pests may take up residence in bluebird houses, it is important to properly monitor the birdhouse to keep bluebirds safe. The data collected, such as brood size, the number of fledglings, and the overall nesting period, can be submitted to different organizations and is useful for citizen science projects.
- Attracting bluebirds: No bluebirds will nest even in a perfect house if the surrounding habitat is unsuitable for their survival needs. Take proper steps to attract bluebirds to the yard by providing bluebird-friendly food, water, and shelter, and these birds will more readily take advantage of the house as a great nesting spot.
- Placement: Put a bluebird house in a wide open area with a clear flight path into the nest. Bluebirds use houses that are placed in full sun and far away from the shade. Also, do not place a bluebird house near bird feeders.
- Unwanted residents: Many other cavity-nesting birds will take advantage of bluebird houses, including house sparrows, house wrens, black-capped chickadees, Carolina wrens, and tufted titmice. Because bluebirds are less aggressive, they are often forced out of their homes. Be aware of these usurpers, and check that they aren't taking over the house before bluebirds have nested.
If You Can't Build a House
While every birder may want to welcome resident bluebirds to their birdhouses, not every birder is equally adept with the tools and woodworking experience necessary to build safe, effective birdhouses. If you can't tell a hammer from a hacksaw, there are birdhouse kits that may be suitable or could be adapted for bluebirds, or you can contact a local bluebird society for assistance.
Creating enough houses for a bluebird trail is an ideal Eagle Scout project, and many local woodworking clubs or classes would be happy to lend a hand with bluebird house construction.
With so many options available, there is no reason for any birder to shy away from becoming a bluebird landlord.