Put your birdhouse “on the market” as soon as you purchase it. You never know when birds may want to vacate their current nest for a safer location or add a second home. That said, most birds look for nests during breeding season (early spring), so make sure your birdhouse is out by the close of winter. In the fall and winter, however, some non-migratory birds may still use the nest, so keep it out year round.
Many birds are territorial creatures and will not live near other birds, so there is a limit to the number of birdhouses you can effectively use. In general, three to four houses per acre should be adequate.
Place your birdhouse away from the prevailing spring and summer winds. In addition, try not to face your house to the west so that you can reduce the sun’s effects on the birds and the house. Most birds, with the notable exception of bluebirds, also prefer the security of trees and bushes. Put the birdhouse where you can see it, but away from noise and activity (including bird feeders) so that the birds can have peace and quiet.
Make sure that your birdhouse is secure and that heavy wind gusts will not topple it. In most cases, you should nail it to a tree; avoid hanging it with rope or a simple cord.
The exact location of your house, however, often depends on the birds you want to attract. If you want to attract bluebirds, for example, your birdhouse should be four to six feet above the ground and facing open fields. Ducks on the other hand, prefer a house facing water that is either ten feet above land or four feet above water.
If you seem to have trouble attracting birds, visit websites such as http://birding.about.com or contact pet stores for helpful advice on attracting and housing the exact birds you want. Try moving your birdhouse to a different location if it has no residents for over a year, and plant annual flowers such as sunflowers and marigold around the birdhouse to attract more traffic.