Challis-Yankee Fork Ranger District - Building a Mountain Bluebird House

Building A Nest Box


  • Use 3/4-inch or 1-inch by 6-inch scrap lumber. Cedar is best. Plywood should be exterior grade. A plank 4 1/2 feet long will build one box.
  • Use aluminum or galvanized siding nails. To prevent nails from splitting boards, first drill nail holes to a diameter slightly smaller than the nails. Before nailing, adjoining surfaces can be glued together with a water-repellent, exterior-construction adhesive.
  • Cut a 1-9/16 inch entrance hole through the front of the box, centered 7 3/4 inches from the bottom. Suitable for western bluebirds and usually for mountain bluebirds, this hole size will exclude starlings. Some "box builders" recommend a 1 5/8-inch hole if boxes are intended for mountain bluebirds. A drawback is the larger hole will admit starlings.
  • Grooves should be sawed beneath the hole on the inside. This gives birds a toehold for easy exit.
  • The bottom should be recessed 1/4-inch. Dimensions will vary with your lumber, so frame the box first, then measure for the bottom. Trimming the corners of the bottom allows water to drain out.
  • The front of this nest box swings open to allow easy cleaning. The hinge nails should not be driven in too tightly and should be directly opposite each other so the front does not bind when lifted up. The bottom of the front is held in place by nails inserted at an angle into drilled holes. Leave 1/4-inch openings at the top under the eave for ventilation.
  • Bevel the roof so it fits flush against the back of the box.
  • The outside of the box may be painted with a light-colored, nontoxic stain or latex paint, adding years to the life of the box.
  • A 5-by-7-inch plastic shield secured around the nest box hole with panel adhesive will prevent flickers from enlarging the hole.
  • Never place a perch on a bluebird nest box as it will invite house sparrows.

Where to put the house!!
This information is reprinted from a pamphlet that was made possible from donations to the Dory Keating Memorial Fund, the Idaho State Conservation Officers Association, and the Idaho Department of Fish and Game Nongame Wildlife Program.

Idaho Nongame Wildlife Program
Idaho Department of Fish and Game
P.O. Box 25
Boise ID 83707