Question

I think we have a wasp nest inside our house somewhere. I’ve seen maybe half a dozen dark wasps flying around inside. They’re freaking me out. How do we find the nest? —S.K., Haverhill, MA.

Answer

We get these wasp calls early every spring, but with our extra long, cold winter, I wasn’t expecting this complaint quite so soon. What you’re seeing are probably overwintering paper wasps, not nesting paper wasps (yet). By “overwintering,” I mean that those wasps have been in your home since last fall. There are many different types of insects that try to move into homes in the fall to escape the winter outside. They rarely do any damage, they just hunker down in a protected place and wait for spring. Of all the overwintering pests, paper wasps might be the scariest, suddenly appearing in your living room, banging against windows looking for a way outside. When the wasps come out of hiding, they are usually sluggish and bumble around, appearing disoriented. They are docile and can usually be captured or killed at this point without much difficulty.

“How Did Wasps Get in My House in the First Place?”

In late summer, when a paper wasp nest has reached its maximum size, new queens are produced. These are the female wasps that will overwinter and begin new nests the following spring. These mated queen wasps usually enter homes around the roofline, through crevices around the soffits, and often end up in the attic space for the winter. When longer days and warmer weather signals that its time to start nest building, the wasps will search for a way to get back outside. That’s when they often end up in living spaces. When paper wasps move indoors for the winter, they usually don’t go very far. If you have quite a few of them inside right now, it indicates that you had some serious nesting going on around your house last summer. The wasps are not building a nest inside your home; they are trying to get outside so they can build a nest, probably on your home. Paper wasps often build new nests in the same general area where they nested the summer before. Paper wasps typically build their umbrella-shaped nests under eaves, on porches, behind shutters, in vents, or around window frames. They will also nest in attics, garages, or in outdoor sites like outbuildings, under deck railings, inside barbecue grills, bird houses, yard lights, junked vehicles…pretty much any place that is shaded and sheltered from weather.

“What Can We Do to Keep This From Happening Again?”

There’s not a lot we can do right now about the wasps that you are seeing inside. There are two times of the year that paper wasps are best controlled so that you don’t have a repeat next year. One, is to block them from nest building on or near your home in the spring. Give us a call; we can do that now. The second is to stop any new queens from moving into your home in the fall. We can do that, too, with our preventive perimeter treatment of the outside of your home. We also offer exclusion services that seal up all those little openings on the outside of your home that pests use to get inside. Give Colonial a call today to prevent nesting wasps this summer. Top photo credit: Jason Milich / Foter / CC BY-ND 2.0 Bottom photo credit: supersum (off) / Foter / CC BY-SA 2.0