Flying squirrels in your house are almost always southern flying squirrels, and they’re more common than most homeowners realize. These small, nocturnal rodents seek out attics, crawlspaces, and wall voids for warmth and shelter, especially from late fall through winter. Because they’re active at night and relatively quiet compared to gray squirrels, an infestation can go unnoticed for weeks or even months before the signs become obvious.
How to Tell Flying Squirrels Are Inside
The first clue is usually sound. Flying squirrels are nocturnal, so you’ll hear activity after dark: soft scratching, rustling, or faint chirping sounds coming from the attic or ceiling. The noises are lighter and quicker than what a gray squirrel or raccoon would produce, which leads many people to assume they have mice.
Droppings are another giveaway, and they reinforce the mouse confusion. Flying squirrel droppings are small, dark, and similar in size to mouse droppings. The difference is location and volume. Flying squirrels tend to leave droppings concentrated near their nesting areas in attics or upper walls, not scattered along baseboards and kitchen floors the way mice do. Their nests are made from shredded insulation, gnawed wood, leaves, fur, and other soft materials, often tucked into corners or between rafters.
One detail that surprises people: flying squirrels are highly social and often move in groups. A single squirrel finding a way into your attic can quickly become a colony. Tree cavities in the wild have been found holding as many as 50 roosting squirrels, and attics offer the same kind of enclosed, insulated shelter. It’s not unusual for a wildlife control operator to find 10 to 20 flying squirrels sharing one attic space during winter.
The Damage They Cause
Flying squirrels chew constantly, and that habit creates real problems. They gnaw through wood, insulation, and, most dangerously, electrical wiring. Exposed wires resting against attic insulation or dry wood create a genuine fire hazard. Even when a fire doesn’t start, chewed wiring causes electrical shorts, power outages, and appliance failures. The damage often happens inside walls, making it difficult and expensive to repair. In severe cases, rewiring sections of the home is necessary.
Beyond wiring, flying squirrels will chew through water pipes, cable lines, siding, and roofing materials. Structural wood damage can accumulate over time if the infestation goes undetected, weakening framing and creating entry points for water. They also contaminate insulation and living spaces with urine, feces, and cached food, producing a noticeable smell as the colony grows.
Health Risks Worth Knowing About
The most significant health concern tied to flying squirrels is sylvatic typhus, a rare but potentially serious illness caused by the bacterium Rickettsia prowazekii. Southern flying squirrels are the only known animal reservoir for this pathogen in the United States. Transmission doesn’t require direct contact with the squirrels. Their fleas and lice shed infectious material that becomes airborne in dust and insulation particles, which people then inhale.
A documented case in New York State illustrates the risk. Two patients developed typhus symptoms after spending significant time on an enclosed porch with flying squirrels nesting in the crawlspace above. Blood testing of 11 squirrels captured from that space showed 100% were carrying the infection. Both patients had heard animal activity above the ceiling before becoming sick. Typhus causes high fever, severe headache, and body aches, and it can become life-threatening without treatment.
Flying squirrels also carry fleas and lice into your home, which can spread to living spaces below the attic. Rabies, on the other hand, is not a meaningful concern. Small rodents including squirrels are almost never found to be infected with rabies and have not been known to cause rabies in humans in the United States.
Getting Them Out
Removing flying squirrels is more involved than dealing with mice or even gray squirrels, because their small size (they weigh about two to three ounces) means they can enter through gaps you might not notice. Any opening roughly the size of a quarter is large enough.
The standard professional process starts with an inspection, typically costing $125 to $250, where a specialist identifies all entry points and structural weaknesses around the attic and roofline. Technicians then set baited traps inside and install one-way exclusion doors, wire-mesh exit tunnels that let squirrels leave but not return. The team checks traps regularly and relocates captured animals. After the squirrels are gone, the attic is cleaned and sanitized, and every entry point is sealed.
Professional squirrel removal runs $300 to $600 on average for straightforward cases. Attic removals tend to cost more, typically $500 to $1,500, because of the number of entry points that need sealing. Flying squirrels specifically push costs toward the higher end of that range, since their small body size means more gaps to find and close. Dead squirrel removal, if one dies inside a wall or attic, adds $150 to $300 depending on the cleaning required.
Poison is not a viable option. Most states don’t allow rodenticide use near homes for squirrels, and poisoned squirrels tend to die in inaccessible spots inside walls or ceilings, creating odor and sanitation problems. They also cache poisoned bait with their food stores, where pets could find it.
Legal Restrictions on Trapping and Relocation
Wildlife regulations vary by state, but many states have rules that catch homeowners off guard. In New York, for example, you can legally trap a flying squirrel that’s causing a nuisance or damaging property, but it is illegal to relocate it off your property. You cannot live-trap a flying squirrel and release it in a park or on public land. Relocation spreads disease, stresses the animal, and creates problems for neighboring properties. If you want the animal removed and released elsewhere, you need a licensed Nuisance Wildlife Control Operator to handle it legally.
Some states classify flying squirrels as protected furbearers with regulated trapping seasons, meaning removal outside those seasons requires a permit. A few states list the northern flying squirrel as a species of concern. Before setting any traps yourself, check your state’s wildlife agency website for current rules on squirrel removal.
Preventing Them From Coming Back
Exclusion is the only long-term solution. Flying squirrels can glide 50 feet or more from a tree to your roofline, so trimming branches back at least six to eight feet from the house reduces their access significantly. Focus on the upper portions of your home: inspect soffits, roof vents, gable vents, and the gaps where utility lines enter the building. Hardware cloth with a quarter-inch mesh covers vents without restricting airflow while blocking entry.
Check the roof edge where shingles meet the fascia board. Flying squirrels commonly exploit small gaps at these junctions, especially on older homes where wood has warped or softened. Seal gaps with metal flashing or steel wool backed by caulk. Avoid using expanding foam alone, as squirrels chew through it easily. Any repair material needs to be metal or metal-reinforced to hold up against their teeth.
If your home has had a colony, schedule a follow-up inspection before winter. Flying squirrels return to familiar denning sites year after year, and a single missed gap is enough to restart the cycle.