Big browns are difficult to get in bat houses and hard to hold in the bat houses.
Usually when the internal temp of a bat house exceeds 95 F , big browns abandon the house.
I have had some success holding them in 6 baffle -7 chamber bat houses.
This summer I am going to make several bat houses using 2" x 10" and 2" x 12" lumber to build some 3 chamber bat houses.
Size will be 2 ft. wide and 3 ft long.
I will cover the 2" material with 1/2" plywood to make the bat houses tight.
The 2" materail covered with the 1/2" ply should help keep internal temp of the bat house from exceeding 95 degrees. These houses will be placed in Wis.
Will paint both houses dark brown.
The roof and 6" of the front of one of the houses will use 1/4" steel on the outside of the bat house.
The steel should act as a heat well to keep bat house temps higher after the sun goes down.
I will weigh the house with the steel on it and let you know what it weighs.
Several different building contractors give me lumber and boards to experiment with. They used to chuckle about my bat house building but now several of them are are quite interested in bats and bat houses.
Kent Borcherding

