Though you may think that the first criterion in selecting a birdhouse is how it looks, in fact that is the last thing that you should consider.
Remember that the purpose of a birdhouse is to give a bird and its family a suitable home, and so you must make sure that the house is up to that task.
First the birdhouse must be the right size.
A house that is too small will not have enough room to hold many babies and the birds will be cramped as they grow older.
Second, the house must be made of the right materials.
Wood or plastic is okay, although wood is usually preferable.
The wood must not be treated with any chemicals, and the inside of the house should not be painted at all.
If you are building a birdhouse from scratch, you are advised to buy fresh, untreated wood.
Using scrap wood can be risky because you don't know if it was chemically treated.
Third, like humans, birds prefer a roof over their head.
The roof should be sloped so water can drain off.
In the event that any water gets inside the house, there should be drainage holes so that it can dissipate.
Fourth, there needs to be adequate ventilation to the house.
Do not purchase a house that has been sealed with caulk.
Fifth, the opening to the house should be the proper size.
It should be just large enough for the adult birds to fit through, but no larger.
The reason for this is to keep predatory birds, raccoons, squirrels, and snakes out of the nest.
It is best if the opening has a predator guard on it this is a piece of metal or hard plastic that will prevent animals from chewing on the house to make the opening larger.
Sixth, finally, is how the birdhouse looks.
Birdhouse is come in many shapes and sizes.
Once you have determined that the first five criteria have been fulfilled, then you should allow your sense of aesthetics to take over in order to pick the birdhouse that will decorate your yard or garden and best fit your style.
Once you have chosen a birdhouse, mount it on a free standing post or pole.
You may wish to put a baffle shaped predator guard on the pole to keep animals from crawling up the pole to get to the babies in the house.
Don't put your birdhouse in a tree because it is too easy for cats, raccoons, and snakes to crawl up the tree to get into the birdhouse.