Who do I need? Hornets behind vinyl siding filter.

December 20, 2023 2:50 PM

We have hornets (or wasps, or whatever) that are coming into our house. I know (roughly) where the next must be, based on observed behavior outside the house. Who do I need to contact, and what should I expect for remediation?

We have vinyl siding on our house. At the bottom of the siding is a section of wooden planking (?). The creatures are seen coming and going outside the hour from under the planking. I've tried spraying under the board, and using a dispenser with a nozzle, behind the board and up to the first layer of siding. This has resulted in no difference in activity inside the house.

So I think I need an exterminator, and they need to be able to remove some portion of the vinyl siding to get to where the next is. But do exterminators remove/replace siding? Do I need a contractor to come out and remove siding until they find the nest, then I contact an exterminator, then have the contractor come back and replace the siding? Or something else?

I'm trying to set my expectations about what to ask for, etc. Thanks for guidance/experience/stories you have.

posted by Gorgik to Home & Garden (8 answers total)

Is the nest currently active?
The next steps may depend more directly on a. where you are, and b. what, exactly, species of wasp you have.

If you're somewhere that has winter, the majority of pest species (yellow jackets, bald face hornets... some say paper wasps but i disagree) have only fertilized queens overwinter, in a site that is not their nest of origin. Thus you could wait until the first hard freeze or so, plug up all the holes inside and out and hope that you've found them all before next spring when queens go looking for new nest sites.

if you're not somewhere that has winter, ask your pest control person.
posted by Cold Lurkey at 4:08 PM on December 20, 2023

We had yellowjackets [these buggers] nesting somewhere inside the overhang over our front door last year, too deep for insect spray to have any effect. We managed to clean them out well before the cold weather set in using a couple of these traps, baited with a couple of inches depth of apple juice (very effective) with a couple drops of dish soap added to break the surface tension and promote drowning of the wasps. Hang the baited traps near where the nest is. Empty out the load of drowned wasps every 3 days or so (if there are live wasps still in the trap, submerge the entire trap in a bucket of water to drown them and then just empty it out into your garden) and rebait with fresh juice plus dish soap. In our case, it only took about two weeks or so until we weren't seeing any more wasps -- evidently our traps were quickly able to slaughter a large enough fraction of the nest's population that there wasn't enough food being brought back to rear replacement workers faster than we were trapping them.

Meanwhile, you need to find the gaps/holes/cracks through which the wasps are entering your house. They can squeeze through very small cracks. Get a tube of caulk and a caulk gun and start sealing cracks. You may also need to get some weather-stripping to close up gaps around exterior doors or windows.

The stuff we read while trying to deal with this emergency seemed to indicate that professional exterminators were far from 100% effective when dealing with a wasp nest that was not physically exposed, and could charge many thousands of dollars for a disassembly/reassembly job that did not always solve the infestation.
posted by heatherlogan at 4:54 PM on December 20, 2023

If the situation inside the house is bad*, you could hang a trap inside as well.

*In my opinion, any number greater than zero of wasps inside my house would count as bad.
posted by heatherlogan at 5:01 PM on December 20, 2023

If they happen to be bees, then you already have a hive with honey inside your wall, and you will need to be able to get to and remove the entire hive and all the honey. It cannot stay inside your wall! It will spoil, drip, attract vermin, cause mold, etc. When this exact thing happened to me, I called a beekeeper, who figured out where the hive was (we could hear it inside the wall from inside the room), drilled a hole to insert smoke, made the hole bigger, removed the bees, including the queen, and then we opened the wall and cleaned everything out without bees present. He took the bees with him to a beehive haven. Additionally, it ls probably illegal to kill bees, which are endangered. This cost a few hundred dollars, I think. We also had to plug the hole in our stucco they were using to enter and exit the outside wall.

If you have wasps or yellowjackets I cannot tell you about the importance of getting to and removing the nest. There are people who specialize in this, though, who you can call.

I had a paperwasp nest in a tree just beyond my front steps a year or so ago. My husband and a friend got a ladder, put on jerry-rigged bee suits (didn't fit well, lots of gaps) and though they cut down the nest it fell on the sidewalk, understandably enraging the army of wasps. They had many stings. Don't do this!
posted by citygirl at 5:55 PM on December 20, 2023

Meanwhile, you need to find the gaps/holes/cracks through which the wasps are entering your house. They can squeeze through very small cracks. Get a tube of caulk and a caulk gun and start sealing cracks. You may also need to get some weather-stripping to close up gaps around exterior doors or windows.

I would NOT do this, yet (you have to eventually, just not yet). If you close the outside holes up, any wasps in the walls will find another way out. That way may be into the inside of your house, through the walls. Ask me how I know!

If you hire an exterminator, they will start by coming with either "dust" or expanding foam. Both contain an active ingredient that is different from what you get in the sprays, and are meant to be tracked in through entrance holes into the main nest as opposed to be directly sprayed. They'll give it a couple days, and come back and hopefully all the activity will be gone, then you seal up the holes. It'll be about 10 minutes of their time. If that doesn't work, the siding will have to come off - but if they can see the access hole and get something in the size of a straw you should be fine. I have a stone house and they were getting in through a tiny crack between stones, so taking it apart wasn't even a possibility.

If you want to give it a cheaper go yourself, get a bottle of that dust linked above and a bulb sprayer. Apply it yourself, after dark - masked, long sleeve shirt, be ready to back away from the area. Repeat the next day if needed. In most cases you won't see any activity after 24-36 hours, then seal the access. If it doesn't work you can always hire a professional.
posted by true at 5:56 PM on December 20, 2023

Sorry I wasn't sufficiently clear about the caulking. Use the caulk inside the house to close up gaps that communicate between the wall cavities and your living space. You can get white latex-based indoor-use caulk for this.
posted by heatherlogan at 6:00 PM on December 20, 2023

Just to add, in Seattle, so freezing winters not necessarily guaranteed. And we can't figure out exactly where the wasps are getting in. There aren't a lot, just one or two a day or so. And they aren't bees.

Thanks for the feedback so far!
posted by Gorgik at 7:14 PM on December 20, 2023

We finally got a long freeze, so as soon as I can we'll be sealing the outside ingress.
posted by Gorgik at 7:56 AM on January 14