They may look cute when they’re munching on acorns in your backyard, but squirrels are absolutely zero fun to have running around your attic. The thing is, your warm, dry attic is basically the perfect shelter for these arboreal creatures, so if they can get inside it, they often will.
Safety Note: Several of these steps may require you to use a ladder. Always observe proper ladder safety, and don’t do any climbing you’re not comfortable with (you’re not a squirrel).
Remove branch-bridges. Squirrels are certainly capable of climbing up and down the side of your house, but they much prefer running along branches. If you trim all of the encroaching branches that are near your house, you’ll go a long way toward preventing a squirrel problem. Trim your branches back so that they are at least six feet from your house. Even the bravest squirrels won’t leap that far.
Locate possible entrance points. Just like mice, squirrels can’t get into your house if you seal all of their access points. Unlike mice, squirrels are Spiderman-esque climbers, so you need to look both high and low for possible entrances. Pay special attention to your ridge and soffit vents (images below), which are classic squirrel-doors. Also be mindful of holes that look like they’ve been created by animal teeth.
Test the holes. If you see any openings, you might already have squirrels inside of your house. Stuff these holes full of newspaper and leave them for two days. If the newspaper is still there, move on to step #4. If it isn’t, there are probably squirrels (or some type of animal) living in your attic. It’s best to remove them (details in step #7) before moving forward, otherwise you’ll trap the animals inside your house!
Seal the gaps. After you’ve located all of the broken vents, holes or chewed out wood, it’s time to seal these areas. The best material to use is a quarter- or half-inch steel mesh screen, which squirrels will not be able to chew through. Cut your screen so that it’s about two inches larger than the hole you’re plugging (this prevents squirrels from gnawing around it) and affix it with a hammer and Brad nails (these are short nails that almost look like staples).
Seal your chimney. Squirrels love chimneys almost as much as they love attics, so it’s worth getting a steel chimney cap, which costs $40-100. Be careful and safe if you install this yourself!
Squirrel warning signs. Even if you’re all meshed-up and protected, a squirrel might still find its way into your attic. Squirrels are active during the day, so a lot times you’ll see them scurrying around your house. You may also hear them inside your walls and ceilings or see teeth marks on the edges of things like your shutters and window sills. The best way to know for sure is to inspect your attic and look for nests, chewed wires and squirrel poop (these are small, black or brown pellets).
Squirrel removal. If you find squirrels in your attic, or strongly suspect they’re up there, the best thing to do is contact a professional. While there are a lot of DIY traps and repellents available, squirrel infestations are complicated and potentially dangerous to handle on your own (squirrels have claws). Leave this job to the pros!