Keeping spiders out of your home comes down to three things: sealing the gaps they use to get inside, eliminating what attracts them (mainly other bugs), and making your space less hospitable. Spiders can squeeze through openings as small as 1/16 of an inch, so even hairline cracks around windows and doors are an open invitation. The good news is that most prevention methods are straightforward, inexpensive, and effective without professional help.
Seal Every Gap, No Matter How Small
The single most effective step you can take is physical exclusion: closing off the routes spiders use to enter. Focus first on windows, doors, and your foundation, since these are the most common entry points. A good quality silicone or acrylic latex caulk works well for cracks around window frames, door frames, and fascia boards. Acrylic latex is slightly less flexible than pure silicone, but it cleans up with water and can be painted over. Clear-drying caulk is forgiving if your lines aren’t perfect.
For larger holes around pipes, wiring, or vents, stuff them with steel wool or copper mesh first, then seal over the top with caulk or expandable urethane foam. Garage doors need a rubber bottom seal (vinyl stiffens and fails in cold weather). Sliding glass doors often have a gap along the bottom track that you can close with 1/2 to 3/4 inch foam weatherstripping pressed into the channel.
Door sweeps on exterior doors make a big difference, especially on older homes where the threshold has worn down. Install screens on any windows you like to open, and check existing screens for tears or loose edges. Walk the perimeter of your home once a year with a tube of caulk and seal anything new that’s opened up from settling or weather.
Cut Off Their Food Supply
Spiders go where the eating is good. If your home has flies, gnats, ants, or other small insects, spiders will follow. Reducing the overall insect population inside and around your house is one of the most reliable ways to make spiders lose interest.
Start with outdoor lighting. Spiders aren’t attracted to light themselves, but they build webs near light fixtures because that’s where flying insects swarm. Switching to amber or yellow-filtered LED bulbs (in the 2200K to 3000K color temperature range) can reduce insect activity near your lights by roughly 60% compared to standard white or blue-spectrum bulbs. That’s a meaningful drop in the prey that draws spiders to your porch, garage, and entryways. When possible, position lights away from doors so insects congregate farther from your home’s entry points.
Indoors, keep food sealed, take out trash regularly, and address any fruit fly or pantry moth issues quickly. Every bug you eliminate is one fewer reason for a spider to set up shop.
Control Moisture and Humidity
Many insects thrive in damp conditions, and certain spider species actively prefer humid environments. The U.S. Department of Energy recommends keeping indoor humidity between 30 and 50 percent. If your home regularly exceeds that range, especially in basements, crawl spaces, or bathrooms, a dehumidifier or improved ventilation can help. Fix leaky pipes and faucets promptly. Standing water in a basement or under a sink creates a microhabitat that supports the small insects spiders feed on, and it invites moisture-loving species like cellar spiders to settle in.
Reduce Clutter and Outdoor Harborage
Spiders need sheltered, undisturbed spots to hide and build webs. Inside your home, that means cardboard boxes in storage areas, piles of clothes on the floor, stacked newspapers, and rarely moved furniture. Switching to sealed plastic bins for storage removes hiding spots and makes it harder for spiders to establish themselves in closets, attics, and garages.
Outside, pull firewood stacks, rock piles, and lumber away from the house. Vegetation touching your exterior walls creates a direct bridge for spiders to walk from the garden to your siding and through the nearest crack. Trim shrubs and tree branches so they sit at least a foot from the structure. Clear leaf litter and debris from the foundation line, and remove any old webs you see on the exterior, as this discourages spiders from rebuilding in the same spot.
Use Sticky Traps for Monitoring
Sticky traps (also called glue boards) are one of the most useful tools for understanding what’s happening in your home. They won’t eliminate a spider population on their own, but they’ll tell you where spiders are active, which species you’re dealing with, and whether your other prevention efforts are working. Brown recluse spiders in particular are readily caught on glue traps.
Place traps flat against walls with the open ends running parallel to the baseboard, since spiders and insects prefer to travel along edges and in dark areas. Good locations include along garage walls, in storage areas, behind furniture, and inside closets. Space them 5 to 10 feet apart in areas where you suspect activity. Check them every week or two, and replace them when they get dusty or full. If your traps are consistently catching spiders in one area, that tells you there’s likely an entry point or food source nearby worth investigating.
Perimeter Insecticide Treatments
If sealing and sanitation aren’t enough, a residual insecticide applied around your home’s foundation can create a chemical barrier. Most spider-labeled products use synthetic pyrethroids, which disrupt the nervous system of spiders and insects on contact. These treatments typically begin working within hours and last 60 to 90 days indoors, though outdoor effectiveness drops to about 30 days due to rain and UV exposure.
Apply these products in a band along the base of exterior walls, around window and door frames, and in cracks where spiders are likely to travel. Reapply every one to three months depending on the product and weather conditions. If you’d rather not handle chemicals yourself, a single professional perimeter treatment in early spring and again in fall covers the two peak periods when spiders most actively seek shelter indoors.
Peppermint Oil as a Natural Repellent
If you prefer a non-chemical option, peppermint oil has the most evidence behind it among natural repellents. A 2018 study found that peppermint oil strongly repelled two out of three spider species tested. Chestnuts also showed repellent effects in the same study, while lemon oil, despite being widely marketed as a spider deterrent, showed no measurable effect on any of the species.
To make a spray, mix 10 to 15 drops of peppermint essential oil per ounce of water. Because oil doesn’t dissolve well in water on its own, add a dispersing agent like solubol to help the mixture blend properly. Spray around window frames, doorways, and baseboards. The scent fades within a few days, so you’ll need to reapply regularly. Peppermint oil is a useful supplement to physical exclusion, but it won’t solve a spider problem by itself. Avoid it if anyone in your household has allergies to mint-family plants.
Precautions for Dangerous Species
Most house spiders are harmless, but if you live in an area with brown recluses or black widows, prevention takes on more urgency. Both species favor undisturbed, sheltered spots: brown recluses hide in boxes, shoes, and folded clothing in storage areas, while black widows prefer dark, ground-level spaces like garages, woodpiles, and crawl spaces.
Always shake out clothing, shoes, and gloves that have been sitting in storage before putting them on. Wear long sleeves, closed-toe shoes, and leather gloves when sorting through boxes, moving lumber, or working in areas where these spiders may be hiding. Sticky traps placed along garage and storage-room walls are especially effective for detecting brown recluse activity early, before an infestation grows. If you have a history of severe allergic reactions to insect or spider bites, keeping an epinephrine autoinjector accessible is a reasonable precaution.