Why Are There So Many Flies in My House?

Dealing with a sudden influx of house flies in your home can be frustrating and unsanitary. This article explores the reasons behind fly infestations, their entry points, and why you might encounter them even in winter.

Why Are There So Many Flies All Of A Sudden?

Several factors can contribute to a sudden increase in flies in your home:

  1. Decaying organic matter: Flies are attracted to rotting food, garbage, and other decomposing materials. These substances serve as ideal breeding grounds, quickly leading to infestations.
  2. Warm weather: Flies thrive in temperatures around 75°F and above. Warm indoor areas like bathrooms, laundry rooms, and spaces near appliances provide perfect conditions for fly eggs to develop.
  3. Rapid breeding cycle: House flies have a short lifespan of 15-30 days, but they reproduce quickly. A female fly can lay up to 150 eggs at a time and produce 5-6 batches in her lifetime, potentially resulting in hundreds of offspring.
  4. Seasonal changes: As temperatures rise outdoors, flies become more active and may seek shelter indoors.

If these factors don’t apply to you, there could be something else going on that you can’t see. Dead animals, including rodents or birds, could attract flies outside of your home. If you live near a farm or have neighbors with livestock, this could also attract more flies to your home. 

How Do Flies Get In The House?

Flies can enter homes through various means, often exploiting small gaps and openings. Open doors and windows are common entry points, especially if screens are damaged or missing. They can slip in through tiny cracks around windows, doors, and vents. Pet doors, unscreened attic vents, and even gaps around plumbing or electrical conduits provide easy access for these pests. Additionally, flies can hitch a ride indoors on people, pets, or items brought in from outside.

Why Do I Have A Fly Infestation In The Winter?

A fly infestation in the winter can be surprising but is not uncommon. Here are a few reasons why you might experience this:

  • Some species of flies, such as cluster flies and fruit flies, seek shelter indoors to survive the winter.
  • Heated indoor environments can mimic the warmer conditions of spring or summer, allowing flies to remain active and reproduce.
  • Winter weather can cause structural gaps to widen, making it easier for flies to find their way inside.
  • Indoor plants, especially if overwatered or decaying, can attract fungus gnats and other small flies.

While flies are more commonly associated with the summer, house flies are still around in the wintertime. Your home serves as a warm environment for them to survive in.