
This picture shows a long french cleat I attached to the top of the mounting board. The 2 narrow boxes are just hanging onto it with no screws or nails.
The farthest box on the right is attached with 2 screws.
The black box on the left was attached 3 years ago with vertical wood strips.
The vertical wood strips and french cleats both provide a gap in back of the box for ventilation and another access.......bats can enter/exit any box mounted on this structure internally...........the orientation is east - west.......
The smaller french cleats shown are left from a previously mounted box........After I took that box down to mount elsewhere I left the small french cleats up to serve as spacers.........
The more I use french cleats the more I like them...........they are a good way to use up scrap wood and make mounting a bat box so much easier!