Members of CARRI have been building and placing nest boxes for a large variety of birds. Below are the dimensions that we use for our nest boxes

Barn Owl Nest Box (6 inch (15.24 cm) entrance hole)

Top       40 X 15 (101.6 cm x 38.1 cm)

Front   40 X 18  including door cut into front door is 13 x 12 (101.6 cm X 45.72 cm), door (33.02 x 30.48 cm)

Sides  18 x 14.25  (X2) (45.72 cm x 36.195 cm)

Back   24 x 40 (60.96 cm x 101.6 cm)

Bottom  18 X 40 (45.72 cm x 101.6 cm)

Cover over top so rain can runoff top 42 x 16 (106.68 cm x 40.64 cm)

*These boxes should be placed on the east or north-facing side of a structure unless placed inside a structure.

Eastern Screech Owl Nest Box (4 inch (10.16 cm) entrance hole)

Front:  12 x 16 (30.48 cm x 40.64 cm)

Left Side: 12 x 16 (30.48 cm x 40.64 cm)

Right Side: 12 x 15 cut in half (3.48 cm x 38.10 cm)

Top: 12 x 16 (30.48 cm x 40.64 cm)

Back: 12 x 26 (30.48 cm x 66.04 cm)

Bottom: 12 x 12 (30.48 cm x 30.48 cm)

*These boxes should be placed in good riparian habitat with large trees and a water source.

American Kestrel and Northern Saw-whet Owl Nest Box (3 inch (7.62 cm) entrance hole)

Front: 10 x 16 inches (25.40 cm x 40.64 cm)

Back: 10 x 22 inches (25.40 cm x 55.88 cm)

Left Side : 10 x 16 inches (25.40 cm x 40.64 cm)

Right Side : (Door on side of Box) 8.75 x 10 inches  (20.30 cm x 25.40 cm), Bottom of side 7 x 10 inches (17.78 cm x 25.40 cm)

Top: 10 x 13 inches (25.40 cm x 33.02 cm)

Bottom: 10 x 10.75 (25.40 cm x 27.30 cm)

*These boxes should be placed at least 15 feet (4.572 m) off the ground, on a post or structure, facing east.

Bluebird/Swallow/House Wren Nest Box (1.78 inch (4.52 cm) entrance hole)

Front: 6 x 9 (15.24 cm x 22.86 cm)

Back: 6 x 13.5 (15.24 cm x 34.29 cm)

Side: 6 x 9 (15.24 cm x 22.86 cm)

Side: 6 x 9 (15.24 cm x 22.86 cm)

Top: 7.5 x 6 (19.05 cm x 15.24 cm)

Bottom: 6 x 6 (19.05 cm x 19.05 cm)

**Our Bluebird boxes open at the top so we can both band the nestlings and clean out the box at the end of the season.