We have found that a three-year warranty is the maximum that can be given without reinspecting the property annually. In the Midwest climate where temperatures can go from -20 to 110 degrees in one year, building gaps will open up over time and provide a new means for bats to enter. We have been in the bat business for over a decade and honor our warranty, ask for references.
Tile, shake, and clay roofs can not be warranted by us. Also, if the building has more of a structural, carpentry issue than a bat problem, the work can’t be warranted.
If we can not warrant the work we do not take the job.