Why Do Bats Sit On The Outside of Homes or Buildings During the Day?
Seeing bats clinging to the outside of your home during the daytime can be alarming. Many homeowners assume this means something is wrong or that bats are trying to get inside. In reality, daytime bat activity on exterior walls, siding, porches, or eaves is more common than most people realize and does not always indicate an active infestation.
This article explains why bats rest on the outside of structures during the day, what it may signal about your home, and when it is simply normal bat behavior versus a reason to take action. The goal is clarity and calm, not panic.
Bats Are Nocturnal but Not Invisible During the Day
Bats are primarily nocturnal, meaning they hunt and fly at night. During the day, they need places to rest, regulate body temperature, digest food, and stay safe from predators. While caves, trees, and rock crevices are their natural roosts, buildings often provide similar conditions.
When bats are seen on the outside of a structure during the day, it usually means one of three things:
They are temporarily resting between feeding periods
They are regulating body temperature
They have been displaced from an interior roost
Common Reasons Bats Sit on the Outside of Buildings
1. Thermal Regulation
Bats are extremely sensitive to temperature. Exterior walls, especially those facing south or west, can retain heat from the sun. Bats may cling to siding, brick, stucco, or stone to warm themselves after a cool night of feeding.
This behavior is especially common in:
Early spring
Late fall
Cooler summer mornings
It does not automatically mean bats are entering the structure there.
2. Resting and Digestion
After feeding at night, bats often need a place to rest and digest insects. Some bats choose to land on vertical surfaces where they feel secure and can quickly take flight again if disturbed.
Porches, beams, exterior trim, and sheltered overhangs provide temporary resting spots that are quiet and protected from wind.
3. Proximity to Feeding Areas
Homes near water, open fields, golf courses, or natural spaces often have higher insect populations. Bats may use nearby buildings as resting platforms between feeding passes, especially if exterior lights attract insects.
This does not mean bats live in the home. It often means your property is near a good food source.
4. Displacement After Exclusion or Disturbance
If bat exclusion work has recently been completed, it is very common to see bats on the outside of the structure during the following one to two weeks. This is normal behavior.
Bats are instinctual animals. When they are excluded from a roost they have used for years, they will return repeatedly to check for access. During this period, bats may:
Land on siding or rooflines
Investigate former entry points
Rest near the structure before moving on
This behavior typically decreases significantly after a short adjustment period.
5. Juvenile or Inexperienced Bats
Young bats learning to fly may land on exterior walls more frequently than adults. These bats are still developing flight strength and coordination and may choose nearby surfaces to rest.
This is most common in mid to late summer when pups begin flying.
6. Sick, Injured, or Weakened Bats
In some cases, bats that are sick, injured, or physically weakened may be found resting on the outside of a structure during the day. Research and field observations show that bats experiencing illness, dehydration, or injury often separate themselves from the main colony or are unable to maintain normal roosting behavior.
Healthy bat colonies tend to favor tight, protected roosting areas. A bat that cannot keep up with the colony, regulate its body temperature, or safely cling inside a roost may end up exposed on an exterior wall, porch, or other surface.
Daytime bat activity combined with unusual behavior, such as difficulty flying, crawling on the ground, or lack of response to disturbance, should be treated with caution. These situations do not automatically indicate rabies, but they do warrant avoiding contact and contacting a professional for guidance.
Does Daytime Bat Activity Mean You Have an Infestation?
Not necessarily, but be vigilant.
Daytime bat sightings on the exterior alone does not confirm an infestation. A true bat problem usually includes additional signs such as:
Guano accumulation beneath eaves or rooflines
Bats consistently entering or exiting the same gaps at dusk
Scratching or chirping sounds inside walls or attic spaces
Strong ammonia like odors indoors
If bats are only seen occasionally resting outside and there are no other signs, monitoring is often sufficient, but caution is needed.
Why Bats Choose Certain Spots on a Home
Bats tend to favor specific exterior features, including:
Rough or textured surfaces they can grip
Sheltered areas protected from wind
Warm surfaces exposed to sunlight
Areas near previous roosting sites
Understanding this helps explain why bats may repeatedly choose the same location even if they are not entering the home.
Can You Prevent Bats From Sitting on the Outside of Your Home?
It is important to set realistic expectations. Bats are wild animals. Just as you cannot prevent birds from landing on a roof or deer from crossing a yard, you cannot completely prevent bats from flying near or briefly resting on your home.
That said, certain steps can reduce the likelihood:
Minimize exterior lighting that attracts insects
Use yellow or amber bug lights instead of white lights
Address obvious roosting ledges or sheltered corners
Install bat netting in problem areas if appropriate
Bat netting is one of the most effective physical deterrents for repeated exterior hanging issues and can be installed in both temporary and long term configurations.
When Exterior Bat Activity Becomes a Problem
Daytime bat activity becomes more concerning when:
Bats are present daily, on a regular basis, and you see more than one
Guano is accumulating on walkways or decks
Bats are entering living spaces
Exterior activity increases over time rather than decreases
In these cases, a professional inspection is recommended to determine whether bats are roosting inside the structure.
Why Professional Evaluation Matters
A trained bat professional can:
Identify whether bats are roosting inside or outside
Locate hidden entry points
Distinguish temporary behavior from an active infestation
Recommend exclusion, netting, or monitoring based on facts
This prevents unnecessary work and ensures problems are addressed correctly the first time.
Conclusion
Seeing bats on the outside of your home during the day can be unsettling, but it is often normal behavior. In many cases, bats are simply resting, warming up, or adjusting after exclusion. Exterior bat activity alone does not always mean bats are living in your home.
The key is understanding patterns. Occasional daytime resting is usually harmless. Repeated activity combined with droppings, odors, or interior sounds is a sign that further evaluation is needed. With the right information and a calm approach, homeowners can make confident decisions without unnecessary worry.