Most people like to have bats around because they provide great bug control, but I just like the bats themselves. I found how to attract bats quite by accident, but the discovery meant I could put old burlap bags and carpet scraps to good use.
I had a habit of storing old rugs and burlap sacks by hanging them over the rafters in my small barn and carport. It wasn’t until much later, when I decided to move this stuff, that I saw there were bats roosting in between the layers. Then I remembered an article I had read somewhere that described how to make a similar type of low-cost bat home.
I used materials I already had, simply laying sections of 1-by-2-inch and 2-by-2-inch lumber onto adjacent rafters, and draping open burlap bags or carpet scraps over them to create a series of curtains.
I have found that hanging the material side by side from one end of the rafters works best. The outer-most curtain should be canvas, carpet or anything else that can block drafts. The bats just need materials they can crawl on and cling to; six to 12 layers works well. Using only burlap bags doesn’t offer the bats enough insulation. The bags are kind of porous and drafty, so the heavier outer-layer material offers extra protection.
Location is important. You want these curtains to be attached to the rafters inside the building so they’re well protected from the rain. They should be close to or against a south or southwest wall, because that’s where the roof will be most warmed by the sun. Also, put them in buildings with high rafters so the bats are not disturbed while you’re working inside.
This method turned out to be more efficient than just hanging the stuff over the rafters because there’s more space for the bats to get into. It’s like replacing a single family dwelling with an apartment building, and it really works.
I think my method is probably the cheapest and most successful way to make a permanent bat house. It also recycles materials that would otherwise go to the dump or burn pile. One word of caution though: Don’t store anything important underneath the bat house — bats have sticky droppings (which do make good fertilizer).
Michael J. Spadoni
Rail Road Flat, California