roaches in attic insulation

Why Are There Roaches in My Attic?

There’s no denying that cockroaches are the bane of every clean household. They eat up your food, lurk in dark corners, and make your home feel dirtier than it is. However, sometimes they pick strange locations to hide. Discovering that you have roaches in your attic – and nowhere else in your house – can be puzzling. They shouldn’t climb up to the highest room of your home, rather than settling in your kitchen – or so you’d think.

Cockroaches will flock to your attic because it’s a safe haven. The pests may crawl in through small cracks or poor weather stripping in the roof. Roaches prefer to reside in dark, damp spaces, so the attic is a desirable breeding ground for them. Depending on the condition of your home, female cockroaches may also lay their egg sacs there. Any rotting wood or old insulation will be an appealing hiding spot and food source.

There are three principles for how to get rid of cockroaches in the attic. These include prevention and sanitation, detection, and chemical control. To apply these treatments well, however, you need to understand the infestation. Eggs, nymphs, and adults will hide in different places and pose different threats.

Can Cockroaches Live In The Attic?

Cockroaches can live in your attic and gain entry by crawling through:

  • Poor weather stripping
  • Gaps in caulking along your rooftop
  • Cracks in your roofing or along your drywall

Once inside, roaches will dwell in the darker, moist areas of your attic. According to Texas A&M University, cockroaches thrive best in climates with high humidity. They also tend to breed a lot more in humid climates. This will only worsen an infestation if not caught in time. That’s especially true when a leaky roof is coupled with the heat trapped by your attic’s insulation.

Roaches In Attic Insulation

Insulation is useful for keeping warm air in your house during the winter. With that said, older attic insulation might invite pests in. That’s because:

  • It’s sealed behind walls or tucked up against the ceiling.
  • It’s warm and offers a balanced temperature in most weather conditions.
  • It can serve as food to the roaches. Despite being chemical-based, many types of insulation also have organic material in their fibers.

It’s wise to replace your insulation every 15 years or so to prevent this. Attic-dwelling cockroaches will feast the insulation itself, along with:

  • Any unsealed soft paper
  • Cardboard
  • Linen stored up in your attic

Roaches are opportunistic and will eat pretty much anything organic within their reach. If they run out of food in the attic, they may use it as a base camp. From here, they’ll sneak out and raid your home for other food.

how to treat roaches in attic

Do Roaches Like Attics?

Roaches don’t like attics in and of themselves. If given a chance, roaches prefer to nest themselves near ample food, like in your kitchen. However, if needed, you’ll find a roach colony picking your attic. These 3 factors will attract them:  

Attics Are Dark

Roaches are nocturnal insects. That means they feel more energized during the night. Since most attics are dark or poorly lit, you’ll find roaches enjoy how the conditions replicate constant nighttime.

Cockroaches may scuttle across your floor in the day as well. However, this is a clear sign that you are dealing with a serious infestation.

Attics See Little Activity

It’s much easier for a cockroach to operate in cover of darkness. Predators and humans who wish to harm them are less likely to be awake at this time. As such, roaches can move about unimpeded and unafraid.

Couple this with the fact that most humans rarely go in their attics. There’s little activity to scare or threaten a roach.

Attics Are Quiet

In that same vein, sounds from around the house won’t easily reach an attic. This creates a quiet getaway for a roach colony to nest. They won’t be startled by pets, humans, or jarring music, which would all indicate predators. This allows the cockroaches to thrive in peace.

How To Tell If There Are Roaches In Your Attic

Keep in mind that seeing a single cockroach does not mean your home is infested. It could be that the one cockroach simply wandered into your home. To know if your attic is infested, you have to see:

These should all be spotted multiple occasions and in succession. Alongside that, you should look out for:

Each of these can indicate that your attic needs extermination measures.

How To Get Rid Of Cockroaches In The Attic

When getting cockroaches out of the attic, you may need to try a combination of treatment methods. Luckily, most are simple to use and implement, even in your attic. According to Colorado State University, there are 3 key ways to effectively manage a cockroach infestation:

  • Prevention and sanitation
  • Detection
  • Chemical control

Prevention And Sanitation

Before you can start finding the places the roaches hide, you need to cast a wider net. Use these steps to isolate the roaches and keep out new ones.

Block Escape

Before you start spraying chemicals, block off all methods of escape. This can include:

  • Cracks in the roof
  • Gaps in the wall
  • Small holes in the floor
  • Openings around windows or vents

Trapping them in that single location will help minimize damage. They can’t eat at your roof or spread into your walls. Likewise, it’ll prevent them from spreading into other areas of your home. Here are a few steps you can take to accomplish this:

  • Install weather stripping or replace older weather stripping
  • Caulk any cracks or plumbing that could lead to other areas of your home
  • Light up any dark places around your attic

Light Up The Space

Most cockroach species become sluggish (and thus easier to catch and kill) in well-lit areas. The University of Zürich proved this clearly. When forced to spend extended periods of time in bright light, cockroaches reduced their movements significantly. Lighting up your attic will make it easier to both see the infestation and eliminate it.

Clean Infested Objects – And Yourself

Roaches may be nesting – or laying eggs – in your stored items. Be sure to clear out any boxes, clothing, or furniture in your attic. If you need to continue using the place for storage, throw out any molded or old cardboard boxes. You can replace them with airtight plastic containers or bags. Roaches find these items difficult to chew through.

Once you’re finished, be sure to clean yourself as well. Roach eggs can easily stick to clothing. Simply tossing your clothes into a laundry basket to clean later is a bad idea. That might accidentally invite the pests into other parts of your home.

Ventilate Your Attic

It turns out that roaches don’t like strong breezes. The Journal of Economic Entomology found that both the American and smoky-brown cockroaches are repelled by air velocities. These must be upwards of 4.0 meters per second.

Fortunately, most standard HVAC systems installed in modern homes produce air velocities that are well above this range. As such, you should try to keep your attic well-ventilated. This can discourage roaches from staying there, and prevent new ones from taking up residence.


Now that the area is prepared, you can start targeting the roaches. The best pest control is applied directly to their hiding spots. But where are they?

Cockroaches tend to concentrate themselves in certain areas. Be sure to set any traps or other pesticides within your attic in:

  • Damp areas under or near plumbing or leaky pipes
  • Cabinets
  • Dark corners

Do not assume the infestation is completely gone if you no longer trap cockroaches in these areas. This may simply mean you need to rotate the traps around different parts of your attic. You will know the infestation is completely gone when your traps no longer turn up any roaches.

Of course, traps alone will not rid your attic of roaches. You should be using traps alongside other types of pesticide.

do roaches like attics?

Chemical Control

Finally, use an insecticide to kill and otherwise rid your attic of these pests. Insecticides tend to come in 4 forms:

  • Residual sprays
  • Non-residual sprays
  • Dusts
  • Baits

Residual Sprays

Residual sprays are insecticides that will leave a toxic residue on surfaces they’re sprayed on. This residue will only last for a certain period of time. Make sure you reapply it within the time period set on the instructions. Of course, you should do this carefully. Aerosol insecticide can spread to your family’s bedrooms if you:

  • Spray an exorbitant amount
  • Fail to block off escape routes, allowing roaches to track it through your home
  • Don’t keep the attic well ventilated

Always follow the directions on the packaging to prevent this. You should avoid spraying any given area too much, as these sprays are poisonous and should not be treated lightly. Likewise, these poisons may damage items in your attic, such as:

  • Linoleum
  • Carpets
  • Drapes
  • Paint

Only spray it on items you’re willing to have damaged, or that can take it.

Non-Residual Sprays

Non-residual sprays will only kill a cockroach on-contact. They typically contain irritants that will lure cockroaches out of their hiding spots and make them easier to kill.  Most non-residual sprays work best when used with residual sprays. The former will flush the roaches out onto the areas coated in the residual pesticides.

Keep in mind that some cockroach species have developed a hardy resistance to these insecticides. The German cockroach is one such case. Do not despair if you do have German roaches in your attic, however. You can pair this method with others to get results.

Dusts and Baits

Insecticide dusts are available in certain hardware stores. This pest control method is designed to kill roaches when sprays are ineffective. For example, you can dust boxes, furniture, or drapes, which would otherwise be damaged by sprays.

Dusts last longer than residual sprays. They can also be spread from roach to roach through physical contact.

Baits should be used in areas that cannot be sprayed or dusted. Place tiny amounts of bait in various locations around your attic. This should easily snuff out most of the other roaches your traps failed to catch.

If you find home treatments aren’t working, you may need to take a harsher approach.

You should see results in a few days or weeks. The population should thin and become nonexistent. If not, your DIY approach may be killing off a few generations, but not all of them.

In this case, it’s wise to call a professional exterminator. An expert will have access to a wide variety of insecticides and equipment that’s not readily available to the average citizen. With their assistance, your attic can become roach-free.