Lord of the Flies
August 9, 2009 4:02 PM   Subscribe

Our house has recently been overrun by an inordinate amount of houseflies. Please help!

Daily, we find 5-10 flies on most of our windows and doors throughout the house (including the finished basement) which reappear regularly after we shoo them outside/kill them. They all look identical (size/color). There does not seem to be an epicenter of the infestation. Our house is clean, with no obvious fly/maggot bait (our garbage was picked up a few days ago with no noticeable decrease in fly generation). We didn't have this problem last summer.

What is the best way of discovering the source of our fly problem? Are there common but non-obvious places that we should look for maggots? If we can't find the cause, what is the best way to deal with it - some sort of non toxin bug bomb?
posted by jpdoane to Home & Garden (14 answers total) 1 user marked this as a favorite
Response by poster: non-toxic. Thats to humans, not flies, natch
posted by jpdoane at 4:05 PM on August 9, 2009

They may be breeding in your drains, bathroom sink or shower or tub. I've had that happen. Drain cleaner or bleach kills that off.

One time I had an infestation of fruit flies that went on for weeks. Eventually I figured out that a former roommate had bought a bag of potatoes and stuck it in an almost inaccessible place under the kitchen counter, a place I didn't even know was a place. Fruit flies had found it and turned it into a fruit fly foundry; it was a mass of maggots.

When it comes to searching for insect breeding grounds, you have to use this kind of logic.
posted by Chocolate Pickle at 4:17 PM on August 9, 2009

While you're searching for the source, good old flypaper works well to keep the numbers down. A tip passed on to me by a friend, is to hang them by a light at night, when all the other lights in the house are off.

Nontoxic, although admittedly a bit unsightly.
posted by cabingirl at 4:24 PM on August 9, 2009

Any funny sickly sweet smell anywhere? Sometimes rodents can die inside a wall.
posted by bonobothegreat at 4:27 PM on August 9, 2009

I just got through a full-fledged disgusting infestation a few weeks ago. There were so many flies, even my cat gave up trying. They coated my window screens of every open window. It was awful. The source was a chunk of wet cat food that had made its way under the radiator in the kitchen and maggotized (stupid kitty!).

In the end, i used three things to bring it under control: 1) flypaper - hanging from a single light fixture in the kitchen (and I left the light on overnight for 3 nights - that helped attract them). 2) a homemade flytrap (I used cat food as bait) and c) keeping all windows and doors closed for 3 full days and nights.

After day three, there was nothing but fly corpses (hundreds. it was disgusting).
posted by Cat Pie Hurts at 4:44 PM on August 9, 2009

We found a long-dead mouse corpse under our stove. Grossest thing I ever saw, but once we removed it and squashed all the maggots, the fly problem stopped. We couldn't smell it by that stage, so you might just have to look in crevices.
posted by nat at 4:55 PM on August 9, 2009

Seconding fly paper to deal with the infestation in the short term.

Are you or anyone in your house particularly sensitive to smell? Do you have a friend who is always complaining about smells that no one else notices? If so, you might just go into the rooms with a higher concentration of the flies and sniff around. It might be worth while to focus around the edge of the room, near cabinets, walls, and furniture where something could be dead or rotting, hidden out of view.
posted by arcolz at 5:14 PM on August 9, 2009

Seconding something dead in the walls. We have the problem on and off with mice dying in the walls. I'll smell that telltale smell of dead rodent and then within a few days there appear the flies. Short of ripping up the walls to find the source, there is nothing we can do but wait it out. It's never been so bad as some of the above stories though.
posted by archimago at 5:48 PM on August 9, 2009

This has happened to me before. I had a constant supply of flies in a room and couldn't account for their existence. I tried to ignore them at first, but then I got a little nuts one night and just started killing and killing them. After a couple of days of making sure I got every single fly, they stopped appearing, even though I never found the "source."

The easiest way I've found (this is one fly at a time, but super satisfying) is to wait until they've landed on something, preferably a pale-colored background, and squirt them with some liquid (water, Windex, etc), making sure the nozzle has the "stream" setting so you can get them from far away. Once they're wet, they're easy to swat. And I second the suggestion about the light -- I'd put the light on in one room and turn off all other sources of light. They'd all congregate in that room and then I'd shut myself in there with them and squirt away.

I feel like the fly paper is very passive. I'd rather go on the offensive and make sure I get them all, without giving them the opportunity to run around laying eggs before eventually making their way onto the fly paper.

Basically if you allow even one fly to hang out around your home, you are letting in the possibility of an infestation. Constant vigilance!
posted by thebazilist at 6:09 PM on August 9, 2009

Oh and I'm one of those "particularly sensitive to smell" people, and I never could find anything.

Flies breeding in the drains are not houseflies -- those are drain flies or fungus flies (we have those, too).
posted by thebazilist at 6:10 PM on August 9, 2009

Are you sure they're house flies and not cluster flies?
I believe they are more common in rural locations.
posted by canoehead at 6:18 PM on August 9, 2009

Response by poster: Well, unfortunately, I think I found the problem. I have water coming into my finished basement. Spent the last hour moving furniture and pulling up carpet. Ugh

Anyway, thanks for the help guys!
posted by jpdoane at 9:04 PM on August 9, 2009

We tried a remedy that worked well last year, but no so well this year...
An example is shown here

there is also a way of cutting a one liter bottle and inverting the top to get the same funneling effect.
posted by exparrot at 7:10 AM on August 10, 2009

I use this stuff when I can't get flies with a flyswatter. It is the stuff, I tell you.
posted by lemniskate at 7:58 PM on August 10, 2009

« Older "Liberal" Media: Y/N?   |   Where to go in Bellevue, Washington and... Newer »
This thread is closed to new comments.