Building mounted bat houses have a higher probability of getting occupied over the pole mounted ones.  Either way both these mountings should be away from tree limbs and power lines.  Their ideal height should be between 15 to 20 feet to safeguard the bat house from possible predators.  The chances of attracting more bats are better in locations within a quarter mile near bodies of water such as rivers, lakes and streams.  Also, results from studies in the US have shown that bat houses facing in a Southwesterly direction will get occupied more quickly.

If you are wondering if there are bats in your area?  Well don't worry.  Bats can be found in every continent except Antarctica.  There may be bats in your backyard right now.  So mount your bat house and see.  They can be mounted any time during the year.  Some bats migrate in the winter to warmer climates while others hibernate.  Bat houses that are mounted in the spring stand a better chance of getting occupied faster when the bat colony is in a growth spurt.  Bats are always looking for suitable housing.  But in some instances bats will not abandon an existing house for a new one.  In this situation it just may take a while. Patience is suggested.  Don't think that your area has no bats.  They are out there.  Give them a chance.