1) First, you've already done the bat inspection process to determine where all the possible entry holes into the building are located. You've recognized the primary entry and exit locations. You've already sealed shut the holes and spaces that the bats aren't actively utilizing, however COULD potentially use to get back in once obstructed out. You've followed my bat repairs process to use correct materials.
2) Second, you've identified the species of bat throughout your bat inspection procedure, by observing them in the attic, by enjoying 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. You've looked into when they have their young (summertime for all species), so that you don't do your exclusion during the bat maternity season.
3) Okay third, now you need to set the appropriate exclusion device on the bat exit spaces and holes. Here is the basic principle: the gadget needs to be set on the exit hole/gap in such a way that the bats have the ability to naturally leave the structure as they always do. They need to crawl out and fly out or flutter down through the gadget. They won't leave the building if there's an obstruction in the method. In addition, the device should be set up so that the bats are unable to fly back in when they attempt to return. Everything involves the way bats take off and land. It's tricky to explain, and this is one of the reasons experience really assists in a successful exclusion. I've seen numerous cases now, and made numerous small changes.
1/4 inch poly netting - a great all-purpose bat web with a small adequate grade to prevent the bats from getting stuck in the mesh or strangled. It needs to be set properly though, to allow the bats to fly out however not fly back in. Making this shape right is an art, like sculpture. I typically set netting on long gaps with clear exit paths. Sometimes you have to extrude the net with brackets to allow enough clearance for the bats. They won't exit the building if there's a blockage in the way.
Window Screen - yes, routine window screen in the house depot, the softest you can find, makes a fantastic exclusion tool (as seen in the photo above). As with the netting, a mix of staple gun or duct tape is an excellent way to protect it to the house. I generally use screening on smaller gaps adjacent to flat surface areas. Make sure there are no spaces on the edges that allow the bats back in!
I do not utilize funnels if there are a lot of bats, since of the traffic jam (metaphorical, not actual, the neck of a bottle would be too narrow). Funnels are best utilized in areas with horizonal or challenging architecture, when the bats are leaving out of a little hole.
Batcones - these are special funnels with a tapered body and attachment wings that you can purchase online.
SUGGESTION: Do at least one dusk bat observation to determine the most popular points of entry and exit. This will tell you where to set the exclusion gadgets.
SUGGESTION: I frequently set these exclusion gadgets in the evening, when a good % of the bats are already out. I've discovered that with a big colony, if a few of the initial scout group does not leave since they are cautious of the exclusion device, that results in a backup. If you do it at night, a number of the bats have actually left when things were clear and simple, and after that the exclusion devices clear out the staying bats within.
Display each night, and if you can get up, at dawn, to see how the bats are responding. If you still hear bat chirping inside or any other sign after the second day, you've done something wrong!
5) After you are sure all the bats are out, remove the exclusion devices and seal the final holes/gaps shut.
Since it's so much easier to find all the gaps and fracture at night while focusing a high-beam headlamp on the structure. You might think this is silly or counter-intuitive, but once again, I've done hundreds of bat tasks, and I've discovered that the work is more reliable this way. You 'd be impressed at the holes you see at night that leave you by day, and the bat behaviors you see that guarantee 100% success.
AID: If you require professional assistance in solving your bat problem, please click on my Hiring Advice and 2018 Directory of Bat Removal Professionals serving every city in the USA.
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