Guidelines For Installing A Bat House

If you're considering installing a bat house in your backyard or garden, you have two options: buy or build. Either way, you'll need to know the correct specifications regarding design in order to ensure the highest chance of occupancy in your bat house. Here are some tips.

Dimensions

Bat houses should be a minimum of 2 feet tall with chambers that are at least 20 inches tall and 14 inches wide. They should also have a landing area of at least 6 inches (this is usually located below the opening).

The number of roosting apartments in a bat house varies, but the general rule of thumb is the more the merrier with a minimum of four. These chambers should be spaced 3/4 to 1 inch apart. Landing areas and partitions need to be grooved at 1/4 to 1/2-inch intervals or covered with square plastic mesh. If July temperatures rise higher than 85 Fahrenheit, you should build vents 6 inches above the bottom of any houses that are 24 to 32 inches tall. If houses are 36 inches tall or taller, vents should be 10 to 12 inches from the bottom.

Materials

If you're building your own bat house, a good choice of construction wood is either exterior plywood, at least 1/2 inch thick, or cedar. Avoid using pressure-treated wood and opt for screws instead of nails. Makes sure to caulk around the roof to close any gaps or seams.

You'll want to stain the exterior of your bat house with wood treatment, preferably three coats of water-based stain. If the average temperatures in July are less than 85 Fahrenheit, use dark colors such as dark brown of gray. If the average July temperatures are between 85 and 95 Fahrenheit, use medium colors, if they are above 95 Fahrenheit, use white or very light stain. For the interior, use two coats of dark, exterior grade, water-based stain.

Mounting and Poles

You'll need to mount your bat house on either a building or on poles. Wood, brick or stone buildings with proper solar exposure are idea choices. If you have a single-chamber house, mount it on a building if possible. You can also mount two bat houses back-to-back on poles, with one facing north and one facing South. All bat houses should be mounted a minimum of 12 feet above the ground. Fifteen to twenty feet is much better. Lastly, avoid placing your bat house near bright lights.

Need more information on bat house construction? Check out the wealth of information at Bat Conservation International.