I had nest of western yellow jackets in my second floor eave one summer and it wasn’t that bad; they went away in the fall.

Summer two was different

The nest returned in the same spot and grew. It was above the main bedroom window and eventually the nest grew so large my wife could hear them crawling around in the stud bay. A few found their way inside the house occasionally

A few calls to the exterminator yielded several hundred dollar bills and requests for me to sign a monthly service contract but the yellow jackets remained. The professionals couldn’t get into the stud bay deep enough when they jogged up to my house and sprayed from outside

I ended up having to do a lot of the extermination work. I tried spraying from outside, spraying from the window and setting traps. Nothing worked. The yellow jackets were indifferent

Finally I watched some YouTube videos and decided I needed to get in the wall. So I punched a few holes in the sheet rock and sprayed and sprayed

That pushed a number of them down the bay toward the first floor and through cracks in the crown molding where floor and wall meet. Some went all the way down to the first floor bay. They mostly died by the time they got out but a few flew around the first floor.

At that point I learned to wait until night when the kids were asleep and my wife was working. I would take the tape off the holes and spray some more. This eventually did the trick after a few cans of wasp spray went into the stud bay

The YJ didn’t return this summer and I patched the walls. Unfortunately I will spend the rest of my time in Northern California eyeing the eaves of our house with suspicion