Many people misunderstand bats. Scary stories and vampire movies have led people to believe bats are dangerous. These flying mammals are actually quite helpful and gentle. They are natural pest removers that can eat up to their weight in insects every night. They also help spread plants and trees by eating fruit and dropping the seeds into the soil. If you want to give bats a safe place to nest, build a bat house, and they will pay you back.
Follow these quick tips to make your bat house feel like home:
- Choose the right location: Place your bat house where it can get at least six hours of direct sunlight every day, as long as the average high temperature in July is less than 100 degrees Fahrenheit (Where the average high temperature in July is less than 80 degrees, your bat house should receive at least 10 hours of direct sunlight). If you can, place your bat house within a quarter mile of a stream, river, or lake. Lots of insects live near water and bats like to live where they can find food easily.
- Make it safe: Like other animals, bats are concerned about predators and won't roost in places where they feel they are in danger. You can make your bat residents feel safe by placing metal predator guards on the wooden poles and by placing your bat house 20 to 25 feet from the nearest tree branches, wires, or other places where predators can perch. Bat houses can also be attached to the side of a house.
- Good Timing: The best time to install the bat house is in late winter, before the bats return to the area in the spring. If you have bats living in your house or garage and you're trying to encourage them to move to the bat house, you should put up the house two to six weeks before evicting them.
To make a bat house, you will need:
¼ sheet (2' x 4') ½" outdoor grade plywood
1 piece 1" x 2" (3/4" x 1 3/4" finished) x 8' pine strip
1/8 mesh plastic netting, 20" x 22 ½'
20-30 1 ¼" rust-resistant or coated screws
1 quart flat water-based paint or stain, exterior grade
1 pint water-based primer, exterior grade
1 tube paintable latex caulk
5/16" stainless steel staples
1" x 3" x 28" board for roof (optional)
- Measure and cut plywood into 3 pieces:
(1) 26 ½" x 24"
(1) 16 ½" x 24"
(1) 5" x 24"
Paint one side of each piece with two coats of a dark color paint.
- Measure and cut pine wood into one 24"-long strip and two 20 ¼"-long strips.
- Put caulk on the 24"-long strip of pine and screw it to the top of the 26 ½" x 24" piece of plywood, on the painted side. The pine strip will be the same length as the plywood piece. Then, put caulk on the other two pine strips and screw them to the right and left edges of the plywood, on the pained side.
- Staple the plastic mesh netting to the plywood on the painted side. Make sure it is flat.
- Put caulk around the edges of the painted side of the 16 ½" x 24" plywood piece and screw it to the back, making a wood sandwich with the pine strips in the middle. Do the same with the 5" x 24" piece of plywood, but leave ½" between the top front piece and the bottom front piece for a vent.
- If you want to add a roof, caulk and attach the 1" x 3" x 28" board.
- Paint the outside of the house. The first coat should be a primer and the last two coats should be exterior, water-based paint or stain. That color should be black where average high temperatures in July are less than 85º F, dark colors (such as dark brown or dark gray) where they are 85 to 95º F, medium colors where they are 95 to 100º F and white or light colors where they exceed 100º F.
- Mount your bat house on a pole or against a building, at least 15 feet off the ground. Make sure the houses are not near bright lights.
This single-chambered bat house can hold about 50 bats comfortably. If you want more bats to live in your house, you can get three or four more pieces of 16 ½" x 24" plywood and a strip of pine the same length as the others for each extra chamber you add. Paint both sides of the interior pieces of plywood and staple plastic mesh netting to both sides. Then caulk and screw the pine strips to one side of each piece of plywood and screw them together in a stack. If you decide to make a multi-chambered house, you must also make vents in the sides that are 6" tall by ½" wide. Or, you can make two bat houses and attach them back to back on a pole.