What Type of Bluebird Nesting Box is Best?

Your choices are many. They include the Peterson box, the front opening box, the side opening box and the PVC box. There are boxes made of cedar, pine, and plywood. No matter which type you build, follow these guidelines:

1. No perch should be attached to the front of the box, for this may encourage house sparrows, which are undesirable competitors.
   
   
2. Entrance holes should be 1-1/2" in diameter for Eastern bluebirds and 1-9/16" for Mountain and Western bluebirds. If the hole is oval, it should be 1-3/8" wide and 2-1/4" long.
   
   
3. Floor dimensions should be approximately 4" x 4" for Eastern bluebirds and 5" x 5" for Mountain and Western bluebirds.
   
   
4. Height from top of floor to bottom of entrance hole should be about 5" to 7".
   
   
5. Opening the box should be easy for monitoring and cleaning. Side- or front-opening boxes are easiest to clean, but top-opening boxes are easiest to monitor.
   
   
6. Ventilation, by means of small holes drilled at the top of the sides or back, or gaps left between the roof and sides or front, should be provided.
   
   
7. Drainage holes, such as holes drilled in the floor, or space between the floor and the sides, should be present.
   
   
8. Attaching the box to a tree or post should be easy. Be sure this has been provided for.
   
   
9. At least 3/4" thick wood should be used as the building material to provide adequate insulation from the sun.
   
   
10. The roof should overhang the entrance hole by at least 1" to 2" to keep out rain and shade the entrance.

" �?Donald and Lillian Stokes in The Bluebird Book"