Summer months are helpful when it comes to identifying the location of bats in the home. Cooler months causes bats to burrow into the insulation. It is very difficult to find them once they move down your walls. The process is much more long term at that point.
Summer months are helpful because they migrate to cooler areas near the roof line. Insulation and burrowing are no longer an attractive method of finding cool areas. So when looking for roosting bats in your attic, start by looking at your calendar.
Bat Roosting Locations
1) Bats roosting near porch line in the evenings due to insect concentration near porch lights.
2) Bats roost near soffit vents or on the actual vent.
3) Bats often roost near or in chimney.
4) Bats roost in your attic roof line.