Best Roofing Systems to Keep Bat Out
If you are planning to get a new roof, the process nearly always removes much of the sealing that we do during a bat exclusion. It is usually best to get the new roof completed before starting a bat exclusion. Make sure that you don't obstruct active entry points and lock bats inside. There are usually plenty of construction gaps to allow bats out, so locking bats inside is rare (but it can happen). Roofers can do a great job keeping water out of the home, but bats are a different story. It will take a team approach.
There are a variety of roofing ventilation strategies to keep bats out of your home. When you build new home, or re-roof your existing one, you have an opportunity to reduce the number of entry points on the home.
Soffit vents - generally keep bats out. These vents allow for the intake of cool air into the attic. Most homes have these vents with a combination of other vents to let hot air out.
Gable vents - These vents come in a variety of shapes and sizes that allow hot air to escape out of the attic. Depending on the particular vent, we usually screen these from the outside to keep bats from roosting behind the louvered cover. Some cover are impenetrable by bats.
Turtle Vents (or old style roof can vents) - These are a pretty good vent to keep bats out. They are not fool proof though, and we do occasionally discover these as an entry point. They are lightly screened on the inside to keep insects out. Over time, these screens may fail. They are installed easily by roofer and form a tight seal. These vents allow hot air to escape. They can be a risk for raccoon entry - especially on single story homes.
Ridge Vents - These vents are a newer style and there are a wide variety of types available. Roofers like to use these vents to allow hot air to escape. But, most of these vents fail to keep bats out - without foaming to structure. There is one type, GAF - Cobra Vent that is nice looking and generally keeps bats out with minimal foaming (at the ends). It is available as a thick roll of fabric. If you must use ridge vents, insist on Cobra Vent. It will look great.
See Ridge Guard for a long term option to secure ridge vents.