How to make a homemade bat exclusion device

While trying to get bats off your property, it is important to know that only one method works best and that is exclusion. Many people offer home remedies that supposedly work in keeping bats away but most of them fail and the bats keep coming back. Bats have great echolocation skills and they will find your home even if you remove and relocate them. Since most bat species are considered endangered, using poison on bats around your home or property may be illegal too. The only safe option is to construct an exclusion device capable of keeping the bats away permanently.  

For exclusion to work, you need to figure out how bats are gaining entrance into your home. Check the exterior of your home for cracks, tears, and any crevices that may be used to gain access. You may also decide to observe the bats in the evenings when they go out to feed and determine where exactly they are coming from. Once you have established this point, then it’s time to build your exclusion device. Building an effective exclusion device can be complex and time consuming and may require you to consult an expert. 

bats under screen

However, if you are confident that you can build it on your own, then you can give it a shot. There are several types of exclusion devices that may be built. Some of them are highlighted below:

Window screen exclusion device

Get flexible plastic netting (0.4 cm or smaller) from your hardware store. Secure the netting unto the exit points you have noted. Make sure the netting extends at least 18 inches below the gap. Make sure the netting is fastened in such a way that bats are able to exit but not enter through the gap. Take note not to make the hole left too small as bats may be discouraged and not fly out from the device. If multiple points of entry and exit are used by bats, make sure to fasten the netting to all the openings. Bats are pretty stubborn and they may refuse to use another exit if the one they use is blocked. 

close up bat exclusion

Therefore, if you notice that the bats are not exiting the building, adjust the netting(s) as required.  Leave the netting on for at least 7 days before removing it. This will ensure that all the bats have left the house before you start sealing up the gaps. You may need to repair wood, joints, and cracked walls after the device has been removed.

Funnels and tubes

Funnels are great devices to build an exclusion trap. If you see small holes that extend inwards on your walls, then you can cut open a bottle or PVC pipe at both ends. They are also sold already prepared in stores. You can also purchase bat cones instead of making them from scratch. Fix the bottle at the opening of the exit point, and leave it there for a few days to allow the bats to exit. 

When fixing the exclusion devices, make sure to do so at night. Most of the bats in your house will be out to get food at this time and that makes their removal easier. Make sure that the devices you have made are sufficient to cover all possible entry areas. Leave the trap for a few
days and do a thorough check to ensure that all the bats have exited your home. If you can still see signs of bats or the bats themselves, then it is possible that you have missed a point or you did not install one of the devices correctly. You may need to reinstall the device and then watch
for signs again. If all fails and there are still bats in your home after all the efforts made, then you should consider bringing in a professional.