Cluster Flies are quite Pestering

By Todd Fratzel on Power Tools, Safety

picture of cluster flyWe’ve had a bit of a fall warming spell this week and the warmth has brought out pestering cluster flies. Cluster flies (Pollenia rudis) are slightly larger than the common house fly and they typically make their appearance on warm fall days or when the weather begins to warm up in the spring.

Cluster flies are attracted to the sunny (warm) side of houses in the fall looking for a protective environment for the winter months. The cluster flies enter into your home through small cracks, holes and openings in the siding. Once the weather warms the flies become active and try to leave the house, flying around gathering on windows and light fixtures.

The good news is that cluster flies do not reproduce in the house house. They are also not interested in food as they actually live off of earthworms outside. The bad news is it’s really hard to keep these pests out of your house. Especially with today’s houses designed for proper ventilation into attic spaces.

picture of bug zapperWe’ve been “terminating” the cluster flies with our cool bug zapper. As you can see in the photo the bug zapper is a really cool “tennis racket” type device that you can “electrocute” bugs with. You push a button and the metal paddle becomes energized, when you touch a fly it get’s zapped dead!

The bug zapper is certainly a great fly swatter and it creates some interesting fun with kids and friends. So if you’re house has become overrun with cluster flies try to relax and deal with them. Feel assured that these are not house flies that are eating food and laying eggs in your home.

About the author

Todd Fratzel

I'm full time builder for a large construction company in New Hampshire. I run their design-build division that specializes in custom homes, commercial design-build projects and sub-divisions. I'm also a licensed civil and structural engineer with extensive experience in civil and structural design and home construction. My hope is that I can share my experience in the home construction, home improvement and home renovation profession with other builders and home owners. I'm also the Editor-in-Chief and Founder of Tool Box Buzz. Please feel free to contact me if you have any questions, suggestions or you'd like to inquire about advertising on this site.

All posts by Todd »

Not what you're looking for?

Search for more articles here. Enter keywords like, 'insulation' or 'kitchens' etc to find your topic.


  1. Liz says:

    What a perfectly timed post! Our attic windows were covered with those thing during a heat wave last weekend. I borrowed my dad’s bug zapper to get rid of the problem – the tennis lesson I took years ago finally paid off!

  2. Sandy says:

    Hi! I found you through Simpson’s Folly. I was practically doing cartwheels when I saw this post! I am SO thankful to learn that they only want OUT and don’t want to stay. I have been plagued with these little buggers ever since we had siding put on our house 5 years ago. They come into the house in droves! Gross! I am going to try to find that really cool bug zapper raquet you have. Hopefully either HD or Lowes will have it.

  3. John says:

    Amazing – my wife is at the cottage this weekend and sends this text “Try Googling – troubleshooting flies in newly built homes. They’re falling in the dry dishes, hair, everywhere!” I’ve been up there each weekend without her, zapping them with the very “tennis racquet” device you mention. There are literally hundreds of them – we have a lot of west and south facing windows, almost floor to ceiling. Thanks for clarifying the species and behaviour (like not reproducing!!!). Anybody else have a solution beyond playing “tennis” all day.

Leave a comment

Be nice. Keep it clean. Stay on topic. No spam.

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Copyright © 2009-2023 Front Steps Media, LLC. All Rights Reserved. Home Construction & Improvement™ is a Trademark of Front Steps Media, LLC.