Wasps coming out of outdoor water heater cover
Wasps build nests inside exterior wall compartments, such as outdoor water heater covers, creating a sudden hazard when trying to access equipment. This makes routine maintenance impossible without triggering aggressive swarms or stings.
What the numbers show
Counted from the threads quoted below. How we count
- The most recent one is from October 2026.
- This comes up 19.0× more often in r/Pestcontrol than across the site as a whole.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
Found another way around this?
Share your steps and trade-offs so fellow engineers don't have to reinvent the wheel. No account required.
- 1considering buying a spray to treat themDid this help you?
- 2willing to pay a professionalDid this help you?
- 3Wait until night or cold weather to remove the nestDid this help you?
- 4Use wasp spray from a distanceDid this help you?
- 5Install adhesive screen repair mesh to prevent future nestsDid this help you?
- 6Calling an exterminatorDid this help you?
- 7Knocking it down with a hoseDid this help you?
- 8limiting time spent out in the garageDid this help you?
- 9keeping all doors closed for several daysDid this help you?
- 10making homemade trapsDid this help you?
- 11waiting until the nest dies off as it gets colderDid this help you?
- 12Sealing up holes in the eaves with silicone sealant.Did this help you?
- 13Scraping the nests off with a putty knife and scrubbing the residue with warm soapy waterDid this help you?
- 14Wiping the seam with peppermint oil to deter them from rebuildingDid this help you?
- 15Checking for other small cracks or gaps where the ceiling meets trimDid this help you?
- 16Keeping sweeping them off the area and spraying Miss Muffets' RevengeDid this help you?
- 17Leave the nest alone and let the insects die out in the winter.Did this help you?
- 18Using a shop vacDid this help you?
- 19Spraying and runningDid this help you?
- 20Using over-the-counter wasp freeze or hornet spray from a distanceDid this help you?
- 21Using dish soap and water in a pump sprayerDid this help you?
- 22Using WD-40Did this help you?
- 23Applying insecticidal dusting powder over several weeksDid this help you?
- 24Buying long-distance wasp killer spray and hunting for the nestDid this help you?
- 25Calling a professional pest control service to open the wall and remove the nestDid this help you?
- 26Installing screens on windows and doorsDid this help you?
- 27Taping up baseboards and putting plastic wrap around outletsDid this help you?
- 28Spraying anti-wasp spray in exterior cracks and gapsDid this help you?
- 29Hanging a brown paper bag filled with newspaper to act as a fake wasp nest decoyDid this help you?
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“I’m just at a lost. They don’t die off, they live in my house all winter. Year after year.”source ↗
“I have this Tagaki outdoor water heater that is due for a flush. I went to open the cover and about 12 or so of these wasps all flew out.”source ↗
“This is what I was worried about. I’m on a strict timeframe and have to move in by tomorrow. There’s no time for it :/”source ↗
“Just had one removed yesterday from our siding - they were flying in through a gap in the hole where our hose is. We’ve been dusting them for the past few weeks but no matter how many we’d find dead in the basement there were still dozens flying in and out when we would go recheck.”source ↗
“So this happened to me and I noticed them the most around a certain window.”source ↗
“Im moving very soon and everytime I go over to the new place there’s at least 2-3 bees inside. I hate having to kill them, I’d rather just have something to keep them away to start with.”source ↗
“Yup. And I’ve just discovered they are yellow jackets and I am feeling very AH at the moment”source ↗
“It's gotten so overwhelming that waiting for them to leave and closing the garage door never works because we at least accidentally trap one wasp, who, just like the rest of them fly in our faces, swoop at us, and harass us.”source ↗
“is there anything i can do to stop this without spending money? any scents or traps i can make? this is getting exhausting to get harassed by angry for no reason wasps.”source ↗
“I knew there was a nest in the walls outside but didn’t think it was this bad.”source ↗
“They're nesting inside my walls and attic. Is there any way to treat them or is my only recourse sealing up all the holes in the eves of my house?”source ↗
“They are flying in an our of my attic through these little gaps in my eves. I hear them buzzing in the walls a couple different areas of my house.”source ↗
“I found a hornets nest in the corner of my house. At the moment, they are far enough from the house that they're not a problem when you sit on the deck. What is the suggestion here to get rid of them? Professional extermination, is this something I can do, with the winter coming up will the nest eventually die in the cold?”source ↗
“New rental. South Houston. This is in the shed. No doors on it, and it's a small yard where me and the dogs walk. Boyfriend has metal legs and cant run well. I said I'd spray and sprint in if he closes the door behind me. He wants to try the shop vac. Suggestions?”source ↗
“had the exact same thing on my porch ceiling last summer. they're harmless, the wasps aren't aggressive and they're actually good for keeping spiders down, but i get not wanting them right there”source ↗
“How / what is best way to remove and keep these from returning.”source ↗
“It’s at the top of the lani wasn’t sure if there were any other tricks to the trade.”source ↗
“had a nest forming under our deck, figured i'd just knock it down with a hose at night like every youtube video says. did not go well, got stung twice and the nest was rebuiltin a different spot within a week anyway.”source ↗
Where this came up
People with this problem also raised
- 4Why won't a ground nest of yellow jackets die?
- 18How to permanently stop bugs coming out of a wall crack
- 3Will an old hornet nest go away on its own?
- 2Is it safe to spray bug killer into walls with electrical wires?
- 6How to stop animals from digging trenches around house foundations
- 5How to stop mice in the roof while waiting for traps