Kenneth Sharpe, Arledge, Patricia M. | 11/4/2013 11:56:31 PM
News Article for August 5, 2013:
As the temperatures have really ramped up over the past several weeks it forces us to confine our most strenuous tasks to early morning or late afternoon. Being out more frequently at dark, I have observed bats flying around catching insects.
Bats are always present in our environment it just seems that we see them more in the summer when we spend more time outside. The flying mammals do need a place to stay during the day so they look for naturally dark quiet areas to roost. Since we do not have a lot of caves in the area one of their choices includes attics in homes and outbuildings such as barns.
I get a number of calls each year from homeowners who have discovered bats taking up residence in their attics. The question is how to get rid of them or make them move.
Bats are very predictable; they sleep during the day and then go out at night to catch insects. They will leave their roost about 30-40 minutes before dark and return the next morning right after the breaking of dawn.
Your job is to determine where the bats are entering the attic. I would pull up a chair to a corner of the house so you can see two edges of the roof line at once. Do this about the time the sun goes down. If you have a helper, put them on the opposite corner so that between the two of you can see all four sides of the roof.
It should be very obvious where the bats are exiting the attic. All of the bats will exit within 15-20 minutes of the first one leaving.
It is possible to have more than one entrance and exit so just see what happens. Your most likely points of entry will be around gable vents due to broken louvers or lack of screens, or cracks around eaves, cornices or vinyl siding. Bats can squeeze through small cracks as small as 3/8 of an inch.
If you are still unclear about the exact location of the exit you can go out the next morning and watch them return just after day breaks.
Once you have determined where they have gained entrance, your job will be to exclude them by repairing the breech. If you have large holes you may need to add wood, metal or hardware cloth. For smaller holes you may be able to just caulk.
Of course you will need to wait for the bats to leave the roost before you make the repairs and it is only necessary to make temporary repairs initially and then you can come back in good daylight later to complete the job with a permanent repair.
If you have multiple places where the bats are coming and going, repair all but one and then give the bats a week to all find the new route in and out before covering the final entry point.
Bats will continue to look for another way back in so keep an eye out to make sure they do not find other ways into the attic.
I have heard and read about all kinds of remedies but exclusion is by far the most effective.