Squirrels often look for safe, dry locations to build their nests, and the attic of a home provides an ideal environment, especially during cold weather or breeding seasons. These animals are rodents, meaning they possess incisors that continuously grow, compelling them to gnaw on materials to keep them worn down. Once inside, they can cause significant and costly damage by chewing through wood and electrical wiring, which poses a serious fire hazard. The compressed and contaminated insulation they leave behind reduces energy efficiency and causes potential structural issues.
How to Locate Squirrel Activity
The first indication of a squirrel intrusion is often the sound of movement overhead, which occurs during daylight hours. Squirrels are diurnal, meaning they are most active in the early morning shortly after sunrise and again in the late afternoon before sunset. Homeowners usually hear scratching, running, or rolling sounds as the animals move around or drag nuts and nesting materials across the ceiling.
Distinguishing the type of noise and its timing is helpful, as nocturnal pests like rats or flying squirrels would be heard primarily at night. You may also hear distinct gnawing sounds as the squirrels work to trim their teeth on wooden beams or other building materials. Upon inspection, look for their droppings, which are small, cylindrical, and pill-shaped pellets often found scattered near entry points or nesting areas.
The most important diagnostic step is identifying the main entry hole, which squirrels may have chewed open in a vulnerable area like a roof soffit, fascia board, or vent. Squirrels only require a gap of about three inches wide to squeeze through, but they will often expand a small opening by gnawing the edges. Locating this primary access point is necessary before any attempt at removal can begin.
Humane Eviction Methods
Humane removal focuses on encouraging the squirrel to leave voluntarily without trapping or harming it. One of the most effective do-it-yourself methods involves installing a one-way exclusion door over the main access point. This device, usually a small metal tunnel with a spring-loaded flap, is sized for a squirrel to push its way out easily but prevents it from re-entering once the flap closes behind it.
Before securing the exclusion door, it is necessary to confirm that no young squirrels are present inside the attic. Squirrels have two breeding seasons, one in late winter and another in summer, and mothers will cause extensive damage by chewing through walls and structural components if they are locked out and unable to reach their litter. Once you confirm the adult has left and there are no young remaining, install the exclusion door directly over the entry hole, allowing the animal to exit and relocate naturally within a few days.
To encourage a quicker exit, you can use temporary deterrents that make the nesting area uncomfortable. Squirrels dislike bright, continuous light and loud, unpredictable noises, so placing a strong light source and a radio tuned to a talk station in the attic can motivate them to leave. Placing rags soaked in cider vinegar or ammonia near the nest can serve as an olfactory repellent to encourage the squirrel to seek shelter elsewhere.
Permanent Exclusion and Sealing
Once you are certain that all squirrels have successfully exited the attic, the next step is to permanently seal all potential and existing entry points to prevent future infestations. This work must be done with durable, chew-proof materials, as a squirrel’s strong incisors can easily tear through common repairs like plastic screening, vinyl, or standard expanding foam.
The most reliable material for sealing gaps is heavy-gauge, galvanized metal hardware cloth, with a mesh size of about a half-inch. This material should be securely fastened over vulnerable areas like attic fans, gable vents, and foundation openings, ensuring the edges are fully secured to prevent prying. All chimney openings should be covered with a professionally installed metal chimney cap to deny access through this common vertical entry point.
Pay attention to the roofline, where the roof meets the fascia and soffit, as this is a frequent breach location. Any damaged or rotted wood should be replaced, and flashing or metal screening should be used to reinforce these intersections. Trimming tree branches so they are at least six to eight feet away from the roof will also eliminate a convenient bridge for squirrels to access the structure.
Sanitation and Damage Mitigation
The final phase involves thoroughly cleaning the attic to remove contaminants and repairing the damage caused by the infestation. Squirrel feces and urine carry pathogens, including the bacteria responsible for leptospirosis and salmonellosis, posing a health risk if the waste is disturbed. When cleaning, wear appropriate protective gear, including a respirator and gloves, to avoid inhaling airborne particles.
Squirrel activity frequently damages insulation by trampling and compressing it, which significantly reduces the material’s R-value and compromises energy efficiency. Contaminated or compressed insulation must be removed and replaced to restore the attic’s thermal condition. Chewed electrical wiring is a serious fire hazard that requires immediate attention.
If contamination is widespread or damage to structural wood or electrical systems is extensive, contact a professional remediation service. These specialized companies use industrial vacuums and sanitizing equipment to safely remove waste, disinfect the area with specialized enzymes, and replace compromised building materials. Professional intervention ensures the space is fully restored to a safe environment.