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Monday, 26 April 2021
How To Get Rid Of Cluster Flies at Home?

How To Get Rid Of Cluster Flies at Home?

Pests are annoying, unsightly, and unsanitary, which is why discovering an infestation is concerning, and cluster flies are no exception. Cluster flies are one of the many nuisances you can find within your home, but do not worry as this guide will help you deal with cluster flies and solve your infestation!

What are Cluster Flies?

Cluster flies are dark grey in color, with small patches of gold hair on their backs and long wings and are 8 mm long. Cluster flies are earthworm parasites that thrive in areas with fertile soil. They do not spread sickness. Cluster flies are commonly thought of as a nuisance when they invade your home in the fall as they get in through crevices and cracks.

Cluster flies lay their eggs in the ground or in the dung of animals. The larvae stay in the ground and hatch when the weather warms up in the spring. The larvae then burrow into the bodies of earthworms and develop into cluster flies. This life cycle typically lasts between 27 and 39 days.

How do I know if I have a cluster fly infestation?

Cluster flies can leave small dark-colored excrement spots on walls or windows, which can be difficult to clean. Another problem with cluster flies is that if they die in places like wall voids or false ceilings, they may attract other pests like larder beetles, also known as stored product insects (SPIs).

What causes cluster flies in the house?

Cluster flies will begin to mature usually in the spring and summer, and when fall comes, these pests seek shelter indoors. In the winter, they're usually only seen inside houses, waiting out the cold. When cluster flies congregate in less-used areas of your home, they may form a horde.

Even though these pests are bigger than the average house fly, they can still enter your home through small cracks and holes in the exterior. Once inside, they prefer to hibernate in unused areas, such as the attic, during the winter.

How do I prevent and control an infestation?

There's not much you can do after the fall except catch cluster flies. So, the best thing to do is to start working on a serious prevention strategy. Cluster flies are one of the easiest flies to get rid of around the house because they are sluggish and clumsy. So, how can you eliminate cluster flies?

Before we jump in, it’s important to add that the following are natural pest control methods. Pesticides present safety and health concerns. If these natural prevention and control strategies fail to work, then contact an exterminator.


Adult Cluster flies do not breed or lay eggs in your home, so if they cannot find a way out, they will just die there. Many people use a vacuum cleaner to suck up the dead flies that entered through the window and door frames. Unless you have a big problem, this may be all you need.

Because they move slowly, vacuuming or even sweeping them out of your home is easy. They congregate on windows because they are looking for a way to get outside. For harder-to-reach or small areas, a small handheld vacuum can be used. Just make sure to empty your vacuum as soon as possible. Empty the vacuum outside if possible, rather than releasing them inside where they will quickly return.

Wait for Spring

If you believe the infestation is small enough to only be a slight nuisance then simply waiting for spring to come is an option. Cluster flies are more common in the fall and winter because they are looking for warmth and shelter as the weather gets colder. The main issue with this, however, is that they will most likely return and it won't’ solve the problem at hand.

Remove Food Sources

Cluster flies love decomposing food, and the sweeter it is, the better. Make sure that perishables are consumed or disposed of before they attract flies to your home. If you have pets, then be sure to remove food and water from their bowl after they have used it overnight to avoid letting cluster flies feast on it. 

When you do dispose of it, make you’re your bin and garbage is sealed and covered otherwise they may be next in it. You do not want to spray pesticides where your food is, it might be a good idea to also invest in some food-safe containers

Sticky Fly Strips

This is somethinFly strips can work if you have an outbuilding or an area that you do not have to look at very often. Many people dislike these because they result in a swarm of bugs clinging to the strip and hanging in plain sightg you certainly do not want in your kitchen or dining room. That being said, they will attract and kill cluster flies for sure.

Remove Standing Water

Because flies need surface water to survive, having good drainage will aid in the prevention of flies. You may be contributing to a big insect problem if you have a lot of standing water or soft spots in your lawn.

Poor lawn drainage is another issue that should be addressed for the sake of your home. Remember though – just because the infestation is in the home does not mean the problem is also outside. An untidy lawn without proper lawn care is a breeding ground for cluster flies.

If you have a moisture problem in your cellar, you can replace or instal a sump pump and/or drainage lines. At the very least, this technique will assist in reducing the moisture load. A little shovelling around the house and lawn care might be able to assist with drainage too!

Existing drainage should be examined for blockages and other problems that can be resolved to restore proper flow.

Seal Cracks and Holes

Seal your house and double-check it:

  • Cluster flies will get into your house through even the smallest cracks or gaps.?
  • Warm attics with plenty of space to hide from predators are especially appealing to these flies.?
  • Cluster flies love to hang out in the cracks between the curtains.?

Cluster flies emerge from spaces in walls and move towards windows when the weather warms up during the day in the winter. This is the most likely time for you to see them.

Cracks can be sealed in a variety of ways:

  • A plain caulk gun and caulk that costs less than $5 a tube can be used to seal small gaps and cracks.?
  • Spray foam insulation can be used to fill larger gaps.?
  • After dark, use a flashlight with another person to check your house for cracks and see if light shows through anywhere.?
  • If you’re alone, another option is to set up a bright light in a room and then go outside to search for cracks.?
  • You can mark locations with chalk and return the next day to seal them.?

True prevention can really only be achieved with stopping cluster flies from entering your home.

Pest Control 

If you have a large infestation, a professional pest controller may use residual sprays to target all active flies and others as they emerge from hibernation. Businesses such as VExtermination, can help you implement effective pest control strategies and get rid of your infestation once and for all.

VExtermination provides residential, commercial, and agricultural cluster fly control services to ensure that your home, business, or farm is cluster fly free. Frequent inspections are the best way to ensure your home is pest-free. 

Frequently Asked Questions

Will cluster flies eventually go away on their own?

Cluster flies that have made their way into your house in the fall to pass the winter will remain hidden and only emerge on warm, sunny winter days to try to get outside through your windows. They will eventually leave when temperatures begin to rise but they never completely disappear if left alone.

Do cluster flies come back every year?

Several species of fly can be found in large numbers in homes in the spring and autumn. When temperatures begin to drop in early fall, it’s common for cluster flies to enter properties in search of a warm place to hibernate. The lofts/roof spaces of houses and farm buildings are commonly used for this purpose. 

These flies will hibernate successfully until the temperatures begin to rise in the spring if they are not disturbed. It's not unusual for these flies to leave a smell that attracts cluster flies year after year to lay eggs in ever increasingly large numbers.