Why Hot Weather Draws Bugs in Your House—And What to Do About It

When the temperatures outside hit scorching levels, you’re probably parking yourself in the coolest spot you can find. And you’re not the only one looking to beat the heat—insects are more likely to try to find their way into more hospitable spots, like your house, when it gets too hot outside for them. So if the start of summer seems to have brought all the bugs to your yard—and your kitchen—you’re not imagining it.

Learn more about the summer insect invasion—including why it happens, how to deter them from your house, and what to do if they’ve already taken up shop.

How Hot Temperatures Impact Insects

Insects are ectotherms, which means they’re “cold-blooded,” and the environmental temperatures have a major impact on them. (That’s why heat is often used to kill off bed bugs, cockroaches, and other insect infestations.) Many insects—including bees and ants—thrive and become more active in reasonably warm temperatures. but once temperatures really climb, it can stress insects out, leading them to look for shelter from the high temperatures. By the time it reaches the 100 to 120 degree range, it can kill off many bug species.

But hot temperatures that don’t hit that danger zone (or are buffered by a cool shelter) can also cause the bug population to explode, says Adham Perriseau, licensed pest management professional at Dr. Killigan’s. “Warmer temperatures accelerate their metabolism and life cycle. Eggs hatch faster, larvae develop more quickly, and adults reach reproductive maturity sooner leading to more generations in a shorter time. This rapid cycle means insect populations can explode during extended periods of heat, especially if food and water are available.” That means that you might see a few ants one day, then suddenly a whole swarm invading your kitchen. (Ew!)

Why Insects End up in Your Home

Just like you, insects are looking to beat the heat when the temperatures rise. “People don’t realize that heat doesn’t just bring bugs out, it brings them in,” says Perriseau. “Insects commonly start moving indoors when temperatures exceed 85 to 90 degrees Fahrenheit, especially during dry conditions, as they search for moisture, cooler shelter, and food. Heat makes bugs more active and often drives them indoors in search of cooler, more humid environments.” So if your home is cooler and has a nice touch of humidity, you’re essentially setting out the welcome mat for them—especially certain bugs, like ants, cockroaches, spiders, earwigs, and flies.

And once they’re in, you may have a hard time evicting them. “Common invaders like ants, cockroaches, and spiders often stay once inside if they find what they need,” Perriseau says.

How to Prevent and Treat Insect Infestations

You might be fine with more bees buzzing in your flowers or more ants outside your house, but nobody wants a bunch of bugs as roommates. And of course, no one wants to bring their homes up to the scorching temperatures outside if they can help it. If you’re in the midst of a bug invasion, or just want to head one off, try these tips to fend off summer infestations.

Apply preventatives more frequently

Whether you’re getting a barrier treatment to prevent them or kill the ones currently invading your house, you may need to apply it more frequently when the temperatures peak. “Most sprays and baits break down or evaporate faster in high temperatures, making them less effective,” Perriseau says. Applying them more frequently—and at the cooler times of day—can help them last longer and provide greater protection.

Double check your weatherstripping

Weatherstripping tends to be something you worry about more as temperatures dip, but reducing air leaks and gaps around windows and doors with caulking, door sweeps, and other deterrents can also help keep you keep cool air in (saving you energy and money) and insects out.

Look out for moisture in and around your home

In addition to cooler conditions, insects seek out humidity and water sources to help them survive—especially if the higher temperatures come with drier weather. That means paying attention to the humidity levels in your house—especially in basements or crawlspaces, where humidity tends to be highest. Installing a dehumidifier, maintaining your air conditioners, and fixing dripping faucets or leaky hoses can ensure that you’re not making

Be mindful of potential food sources

Leaving out fruit, pet food, or other tasty treats can encourage insects to drop on by—so storing food in sealed containers or the fridge, putting leftovers away promptly, and cleaning dishes can help deter bugs.

Keep trash bins away from your house

Trash attracts all kinds of pests to your house, from insects to large animals like raccoons. Storing garbage further back in your yard—or at least, a few feet away from your house—will avoid attracting them and encouraging them to seek shelter in your home.

Trim back hedges and other greenery

Tree branches and shrubs—or even mulch—that touches your house can provide a bridge for insects to invade.

Try natural deterrents

Some essential oils, such as peppermint, lavender, or citronella, or a layer of diatomaceous earth encircling your home could help keep the creepy crawlies at bay, Perriseau says.

Be fast about treating infestations

“With longer, hottersummers becoming more common, staying proactive before bugs settle in is the best way to avoid serious infestations,” Perriseau says.

“To quickly evict bugs, locate and eliminate their entry points, food, and water sources,” Perriseau says. He suggests bait traps, natural insecticidal sprays, or natural remedies such as diatomaceous earth—plus regular vacuuming sessions to remove insects and eggs. “Acting fast and consistently is key to preventing them from settling in and multiplying.”