Bats are beneficial animals, able to consume hundreds of insects per hour for food. Unfortunately, bats are prone to roost in attics, and can cause damage to insulation and wood over time. There are many different approaches to take to get your bats out of your attics. Here are a few.
Timing of Bat Removal - The Dos and the Donts
The timing of your bat exclusion is critical. Bats breed in the spring, typically giving birth in May. Bat exclusion must be done between August and May, as the baby bats are unable to fly during most of the summer months. In addition to being subject to inhumane treatment, baby bats left behind from a poorly timed exclusion will create other problems. Early spring or early fall are the best times for a bat exclusion.
You will need a few people to help watch your roof line at dusk, to make note of the exit points used by the bats. Watch over a few days, and make note of all locations where bats are seen flying out of the house.
Finding an Alternative Bat Home
Bats have a keen sense of location, and will return to their nest by instinct. A bat house can hold a hundred or more bats and is easy to make. Bat houses are also sold commercially and typically cost between $15 and $50. The higher your mount a bat house, the more likely the bats will use it. Hang your bat house very close to one of their favored entry points to your attic, and you will increase your odds of their taking up new residence there.
Depending upon the nature of the bats’ exit routes, you may use bat cones or hardware cloth screens to allow exit while blocking entrance. A bat cone is a small, narrow tube that angles down sharply, with a slippery interior surface. Bats can fly out, but not back in through a bat cone. Install bat cones in any hole that will accommodate them. Otherwise, for small cracks, use duct tape to secure hardware cloth screen over the crack on the top and 2 sides, leaving the bottom unsecured. The bats will be able to wiggle through the opening, but not back in.
Watch your roof line for a week after taking the steps above. After you have verified that the barriers have worked effectively, remove the bat cones and screens and seal the holes and cracks permanently. Silicone caulk is best for the task of sealing small areas, and in some cases you will need to install screen hardware cloth permanently over vents that need airflow.
Removing Bat Odor (Reducing the Laws of Attraction!)
The odor produced by the guano and urine build-up will continue to attract the bats in subsequent seasons. Waste and odor removal are also important for a healthy interior environment. Use an odor remover with enzymes for the best results, and replace any damaged insulation.