There’s nothing more annoying than a fly buzzing around your head while you’re trying to cook a meal, cozy up with a good book, or take an afternoon nap. Even in the wintertime, these pesky little insects make their way into our homes and stay well beyond their welcome. How can we kick flies out of our homes for good?
Flies most commonly enter homes through small cracks in the building, where they’re drawn to warm air seeping through those openings during the winter. Block these areas of entry, and then use commercial or homemade fly traps to eliminate them.
Better yet, this can often be done without the use of chemicals! If you’re fed up with flies taking over your home, read on to learn about the 6 best ways to get rid of house flies in the winter.
* This post contains affiliate links.
What Attracts Flies Inside Your Home In The First Place
It’s fair to say that most people would prefer that flies stay in the great outdoors, but unfortunately, many types of flies have adapted to living right alongside humans.
You might think, “What do they want to do with us?” Well, just like humans, flies like to cozy up for the winter in a warm environment. There are several areas around the home that draw them in and encourage them to stay awhile.
Cracks and Crevices With Warm Air
In late fall, flies like to make their way into a warm home for winter shelter. According to information published by the University of Missouri, flies can detect warm air seeping through small openings in the home. They gain access to your home through these openings and take shelter in cavities behind walls.
The most obvious entry points are open doors and windows, but you might not know that flies can enter through teeny-tiny spaces that you may not even notice. These can include small gaps around door and window frames, damaged screens, or cracks in the foundation of a home.
Once flies enter, they migrate upwards and are often found in attics or top floors where the air is warm.
If you’d, take a look at our full guide on how flies enter your house to learn more about the nifty ways they find their way inside!
Exterior Lighting
Turning on your porch lights at night gives your home a warm, welcoming glow, which unfortunately is also very welcoming to flies.
At night, these lights are a beacon that encourages flies and other insects to congregate right at your front door. Once you open that door, all they have to do is fly right in!
External lighting fixtures in your home also shed light on cracked windows or other small openings, where flies can easily enter.
Icky Odors
Another very attractive aspect of your home to these winged creatures is your garbage. Many types of flies feast on the cocktail of banana peels, coffee grounds, and other spoiled food that’s probably present in your garbage can. Yum!
Once the flies are nice and full, they’ll likely stick around to see if they can find a warm place to sleep off their meal. If they detect warm air coming from your home through those cracks and crevices, they’ll surely invite themselves in.
Your first line of defense for deterring flies from entering your home is to block their entry!
You should first inspect your home for small openings that flies can squeeze through. We know this sounds daunting, but just take it step by step! Here are a few common sites where flies gain access to your home.
Check these areas to ensure they’re properly maintained:
Screens over doors and windows
Cracks or crevices around windows
Under soffits (the exposed siding where your roof hangs over your house)
Ventilation openings
Cracks or crevices on the exterior of the home (siding, foundation, etc.)
Researchers at the University of Missouri suggest that you regularly inspect screens around your home to make sure they’re in good condition. Install more screens if needed, especially around doors, windows, and even vents. Doing so will allow you to get some fresh air on a nice day without letting the bugs in!
If you find any cracks or small openings in the exterior of your home, be sure to seal them with caulking or foam. Check out this Loctite TITLE FOAM Insulating Foam Sealant. The product seals gaps and cracks around your home, and is even UV resistant!
It’s especially important to inspect, seal, and repair these areas by Labor Day before the weather gets colder outside (and then warmer inside.) This will ensure you keep out the cluster flies, who like to make their way into the home beginning in the fall.
You might think keeping the inside of your home fresh and clean is enough to discourage flies from hanging around, but make sure not to neglect the outside of your home! How long has it been since you cleaned out that outdoor garbage can?
House flies especially love feasting on rotting food, so a dirty garbage can is going to direct them right to your house. To prevent this, be sure to clean out your garbage can or bin regularly, and make sure it has a tight-fitting cover.
If you have pets, it’s also important to dispose of their waste properly to discourage the attraction of flies to your home.
You can also take certain sanitation measures inside your home to prevent flies from coming inside. Try not to leave food or beverages sitting out for long periods of time, or cover them tightly if they must be out.
Also, be sure to take out your garbage at least every 4 days, and cover your household trash with a tight-fitting lid. Rotten fruits and vegetables also attract flies, so be diligent about disposing of those before they spoil.
3. Set Up commercial Fly Traps
While blocking entryways and maintaining proper sanitation should significantly lower the fly population in your home, a few might still sneak inside. Don’t worry! The next few sections focus on deterring and eliminating flies if they’re already inside your home.
A common, and effective, way to get rid of flies in the home is to use traps. This section specifically talks about commercial traps and offers some helpful tips and tricks.
Fly traps aren’t effective when used alone, as they only temporarily solve your infestation problem. They should be used with other methods, such as exclusion (blocking entryways) and sanitation.
Two common types of commercial traps are:
Resin strips (“flypaper” or “fly strips”)
Light traps
Flypaper
Flypaper is an easy and inexpensive method of fly control in the home. These sticky strips are usually coated in a fragrant, sweet substance that attracts many types of flies.
Flies like to rest on vertical surfaces, so it’s best to hang your flypaper in a vertical position near sunny, warm spots in your home. Check out this Black Flag Fly Paper, which is suitable for both indoor and outdoor use!
Here are some general tips for using flypaper in your home:
Hang the paper in a vertical position in an area with low air movement
Place the strips in sensitive areas such as over your garbage or in your kitchen
Use one strip for every 1000sqft of property. You can use more if rooms are divided
Replace your fly strips every 2-3 months
Light Traps
We’ve already learned that flies are attracted to light, so why not lure them in with a light trap?
Essentially, light traps work by emitting wavelengths that are most attractive to flies, and they contain strips of sticky paper that trap the fly once it lands on the light. While they’re more expensive than flypaper, they are a very effective method of indoor fly control.
Install no higher than 4-6 feet from the floor (flies are generally more active below eye level)
Position in a dimly lit area of your home to lure in the flies
Install at least five feet from your kitchen or other areas of food prep (because, ew)
Replace bulbs at least once a year
Clean your traps regularly
Supplement the light traps with fly paper traps for more effectiveness!
4. Use Vinegar, Sugar Or Honey To Trap Flies
While you can easily order a fly trap online, you can also make a fly-trapping concoction from ingredients that are likely already in your home!
These homemade baits usually have a base of cider vinegar, yeast & sugar, or banana. House flies are particularly attracted to a mixture of sugar and yeast since its scent signals that it provides a source of food for them.
Grab a one-pint glass jar (a mason jar would work well!) and fill it with ⅓ cup of warm water (not boiling).
Add in a package of activated dry yeast and mix with one teaspoon of white sugar and wait a few minutes. The sugar will activate the yeast and create a foam.
Grab a small plastic bag and place it over the jar, keeping one corner of the bag inside the jar.
With a pencil or sharp object, poke a small hole in the bag’s corner.
Place a rubber band or canning ring around the jar to secure the bag in place.
Watch your homemade trap attract all the flies!
You can also DIY fly bait with an old plastic bottle and some honey! You can grab an empty plastic drinking bottle and cut off the top (just below the neck). Invert the top into the base of the bottle so it creates a funnel and attach with tape or glue. Then, simply fill the bottom with sugar syrup or honey!
The flies will be attracted to the sweet mixture at the bottom and get stuck as they try and get out.
5. Utilize A Handy Fly Swatter!
We know we’ve talked about some fancy methods of fly control, but don’t underestimate the power of the classic fly swatter!
Fly swatters are an effective method of fly control if you have a few individual flies roaming about your home. Fly swatters are great to have on hand so you don’t have to smoosh a fly with your hand (ew) or roll up mom’s favorite magazine or dad’s newspaper.
Another physical method of fly removal is a vacuum cleaner, which works well for clusters of dead flies in your attic or other areas of your home.
6. Flies Hate Chemicals
We should first note that, insecticides and other chemicals should be a last-resort measure of fly control. You should first go through all the steps above when dealing with a fly infestation in your home. With that said, there are various types of insecticides on the market, including:
Baits
Liquids
Aerosols
Dusts
These commercial insecticides are mostly sold over the counter and are usually available in hardware and nursery stores.
You can also use natural scents that flies dislike to confuse their sense of smell and cofnuse them. Check out our full list of scents that flies hate here!
The Most Common Flies To Find In Your Home During Winter
Now that you know the various ways that flies can enter your home, let’s go over the three most common types of indoor flies you’re likely to find in your home during the winter months.
It’s important to identify the type of fly that is invading your home and to know its feeding and invading habits. Once you know these things, you’ll be able to take specific measures to keep them from coming back!
Cluster Flies
According to Colorado State University, cluster flies are the most common type of “overwintering fly,” meaning that they seek shelter during the cool months. As their name suggests, cluster flies hunker down for the winter in “clusters,” where they often remain dormant and inactive.
Because they exclusively feed on earthworms, cluster flies aren’t attracted to odors emitting from your home.
Instead, they are attracted to “leaks” of warm air emitting from your home in late fall. Cluster flies enter your home in late August or September, where they find a cozy spot in your upper floor or attic.
While they often remain dormant, cluster flies sometimes venture out of their hiding places if the temperature is particularly warm. They are considered nuisance pests for this reason, and they don’t contaminate food or bite.
Besides their annoying habit of buzzing around your head, cluster flies can also be a concern for homeowners when they form large clusters in attics or accumulate around windows, according to a study conducted by the University of Guelph. Talk about unsightly.
Tip: You can identify a cluster fly by its dark gray color and golden hair on its back.
House Flies
House flies are the most well-known and common type of indoor fly. They love to hang out with humans, but they’re no “Man’s Best Friend!”
Like cluster flies, house flies also “overwinter” inside the home. They are also attracted to warmth emitting from a home, but their feeding habits differ from those of the cluster fly.
Speaking of feeding habits, if you’re currently eating, come back to this section later. It’s pretty gross.
So anyway, house flies feed on manure, dead organic matter, garbage, and rotting fruits and vegetables around your home.
House flies prefer liquid waste because it’s easier to digest, but they also like to feed on sugar and other solid foods. To digest solid food, they have to regurgitate it (are you grossed out yet?) and then consume it in liquid form.
Truthfully, you really don’t want that to take place.
Tip: You can identify a housefly based on its gray color and the dark stripes on its back!
Do you know those large, shiny flies that appear to be a metallic blue, green, or black color? Those are blow flies!
These flies normally breed and reproduce outdoors, but in the cold winter months, they seek shelter inside buildings.
Unlike cluster flies, blow flies are active during cold months and may even lay eggs and reproduce if indoor conditions are right.
Similarly to house flies, blow flies feed on garbage and other decaying matter. They are also attracted to gas leaks in the home.
Here’s an even more stomach-churning fact: blow flies sometimes feed on deceased animals, such as mice, behind the walls of a home. But don’t worry, this isn’t likely to cause a major infestation, since the flies only like newly deceased animals.
Let’s Recap!
Wow, that was a lot of info! Let’s quickly go over a few important points:
Flies are most likely to make their way into your home through small cracks and crevices.
The best way to avoid infestation is to inspect your home for small openings and seal them with foam or caulking. You should also tightly cover garbage cans inside and outside your home.
Commercial traps, including flypaper and light traps, are an effective method of fly control.
You can create inexpensive, homemade traps to “bait” flies in your home.
Fly swatters are a great way to eliminate a few individual flies hanging around.
Insecticides are an effective method of fly control but should be used as a last resort. Follow all label instructions or contact a professional for help.
We hope you now have the knowledge and confidence you need to control and avoid fly infestations in the winter!
References
Alpert, G., & Frye, M. (2014). Sanitize to Manage Those Blow Flies. NYS Integrated Pest Management Program.
Hinkle, N. C., & Hogsette, J. A. (2021). A Review of Alternative Controls for House Flies. Insects, 12(11), 1042.
Jewiss-Gaines, A., Marshall, S., & Whitworth, T. (2012). Cluster Flies (Calliphoridae: Polleniinae: Pollenia) of North America. Canadian Journal of Arthropod Identification, 19, 1.
Robyn is your friendly neighborhood writer, editor, and published author - boasting many years of experience in pest control, from which she magically weaves words into the captivating and engaging posts as we know them. When not tucked behind her laptop screen, she can be found embracing nature in the most thrilling ways possible. Rock climbing? Yes, please! Hiking? Absolutely! Traveling the U.S. with her husband, their lovable three-legged dog, and two mischievous cats? That’s her everyday reality. They live, love, and work in their cozy campervan, letting the road take them where it will, and finding inspiration in every sunrise, mountain peak, and wildlife sighting they encounter. Check out my Profile.
Pest Pointers was started in a cozy corner of Upstate New York, known for its expansive pastures, dense woods, and abundant wildlife pests. We are dedicated to providing YOU with solutions and insights into managing common pest issues. Starting out on over 50 acres of land and a freshwater bass pond with abundant pests, we combine firsthand experience with dedicated advice to help you tackle even the toughest of critters!