Bat Exclusion Methods – The Bat Proofing Process
The long-term solution for bats that enter buildings and cause a nuisance problem or present a public health hazard is to systematically repair the structure. Chemical toxicants never solve house bat problems and often create different, more dangerous problems. This section describes bat-proofing techniques that when used in conjunction with an effective bat house will effectively deal with house bat problems. Recent declines in bat populations and greater appreciation of the ecological importance of bats have led to this solution which encourages bat conservation, protects human health, and permanently solves nuisance problems.
The following are typical steps involved in the bat exclusion process to humanely remove bats from your attic or home and prevent them from reentering again. This process is also referred to as bat-proofing.
1) Once the bat inspection process is completed – it has been determined where all the possible entry holes into the building are located, the primary entry and exit areas were identified and the holes and gaps that the bats aren’t actively using are sealed – you’ll move forward in repairing the areas that show bat damage using the proper materials.
2) The species of bat is determined during your bat inspection process, by observing them in the attic, by watching them fly out of the house at dusk, and by examining the bat poop that you see in the attic or the ground below the entry holes. Research should be done when they have their young (summer for all species), so that you don’t do your exclusion during the bat maternity season. The bat birthing period for most areas is May – July. So goes the saying, “May through July – let them fly.”
3) The proper exclusion device should be set on the bat exit gaps and holes. Here is the general principle: the device is set on the exit hole/gap in such a way that the bats are able to naturally exit the building as they always do. They have to crawl out and fly out or flutter down through the device. They won’t exit the building if there’s an obstruction in the way. In addition, the device must be configured so that the bats are not able to fly back in when they attempt to return. It all has to do with the way bats take off and land. It’s difficult to describe, and this is one of the reasons experience really helps in a successful exclusion.
4) Leave the exclusion devices up for at least three days to be sure. Monitor each night, and if you can get up, at dawn, to see how the bats are reacting. If you still hear bat chirping inside or any other sign after the second day, you’ve done something wrong! Remove the exclusion devices immediately and start over.
5) After you are sure all the bats are out, remove the exclusion devices and seal the final holes/gaps shut.