Helpful hints for all birdhouse constructions:
1. Make a hinged roof or one wall so you can easily clean the house each spring — before April is a good time. Use rust-proof hinges to make this task easier. Nimble-fingered raccoons can open a hook and eye!
2. Drill at least four 1/3-inch holes in the floor for drainage, and two 5/8-inch ventilation holes near the top of each wall of the house.
4. The walls of the house should enclose the floor to keep rain from seeping into the house and nest. Recess the floor ¼ inch up from the bottom of the sides to discourage rotting.
5. Don’t put perches on any bird house. The only birds that prefer them are starlings and house sparrows.
6. On songbird houses keep entrance holes 1 3/8 inches or smaller to keep out starlings and house sparrows.
7. Space nest boxes at least 25 feet apart (300 feet for bluebird houses) to reduce conflicts. Most birds are territorial and protect the area around their nest.8. The inside wall, just below to entrance hole, needs some deep horizontal scratches or grooves. When the birds are ready to come out, they can grab these edges with their toenails to help them climb up and out.
10. Other animals may take up residence in your boxes, including mice, squirrels, bees and wasps. Do not use sprays. You can either very carefully remove them or put up a few more boxes to make room for everybody.
11. Most houses should be attached to a post, building or tree. Bluebird boxes should not be placed on trees because of cats and raccoons. They are best mounted on poles up high.