Bat House Plans
Links for Bat Houses
Reasons for Failure
Features for Success
Size: Houses should be at least 24 inches tall, at least 14 inches wide and have a landing extending below the entrance at least 4 inches
Size of Roost Chambers: 3/4 to 1 inch apart
Number of Roost Chambers: The more the better (3 - 5 is good)
Internal Wood Surface: Grooved horizontally at 1/2 inch spacing or mount 1/8" or 1/4" plastic mesh covering one side of each roost
Material: Exterior plywood 1/2" and Cedar (no chemical treated) - caulk all seams, especially roof
Roof: Galvanized metal keeps the house dry.
Vents: If average July temps are above 85 degrees. Six (6) inches from the bottom, 1/2 inch wide and running the length of the house
Exterior Paint: Three coats of exterior grade water-based stain. Don't use oil-based as it will poison the bats. Paint will fill the groves and smooth out the surface.
Sun Exposure: At least six hours of direct daily sun light (South or South-East) if average July high temps are less than 100 degrees F
Mounting: At least 12 feet off the ground and 15 - 20 feet is best. Mount on a pole or side of a building under the eaves. Buildings with wood siding or masonary are best. Entrance not too close to tree branches and safe from predators.
Installation Time: Before bats return in Spring. March is best.
taken from The Bat House Builder's Handbook, 2001 printing, copyrite
1993 by Bat Conservation International, Inc.