Cluster Flies

What Is Are Cluster Flies?

They are black with short, yellow hairs on their thorax and wings that overlap while resting.  Adult Cluster Flies, which are a little larger than common houseflies, range in size from 3/8 to ½-inch long.

Why Do I Have Them?

Cluster flies survive winter by hibernating inside wall void and attics of homes and other buildings.  They enter through foundation cracks, gaps in siding, attic vents and other small openings in the early fall.  They remain mostly dormant over the winter but are likely to be annoying on warm, sunny winter days when some become active.

Are They Dangerous?

Cluster flies are primarily a nuisance and do not cause any harm to people or property.  

How Do I Get Rid Of Cluster Flies?

Getting rid of flies can be a difficult task as they overwinter in hard to find areas.

Can I Do It Myself?

Do-It-Yourself cluster fly treatments and products are not usually effective and may only eradicate a few of the flies and not the entire cluster fly population.  They may also contain pesticides that can be harmful to people and pets if they are misused or mixed improperly.

How can I prevent this in the future?

Preventing cluster flies is not easy but sealing cracks, holes and openings that lead inside can help but the most effective way to control cluster flies is by contacting a professional pest control company.