Discovering a large wasp inside your home can be alarming, especially when it appears sluggish or is crawling along a curtain. While it is easy to assume that a hidden nest must be inside the walls, a single wasp does not necessarily mean there is an infestation. Wasps can accidentally enter through open windows, doors, cracks, vents, or even arrive indoors on clothing and bags. Toward the end of the warm season, they can also become slower and more disoriented as temperatures drop and food becomes harder to find.

Paper wasps are particularly likely to appear indoors during late summer and early fall. As their active season ends, worker wasps die off while queens look for protected places to survive the colder months. Cooler indoor temperatures can leave these insects with less energy, which may explain why one is crawling instead of flying. Curtains near windows are common places for them to rest as they try to find their way back outside. “Their sluggish behavior indoors is often due to the cooler indoor climate and lack of food.”

The strongest signs of a hidden nest are repeated wasp activity around one particular opening, such as a crack, vent, or gap near the roof. You may also hear faint buzzing or rustling coming from inside a wall. Increased activity around eaves and soffits can be another warning sign. These clues are much more meaningful than simply finding one wasp indoors.

If you find only one wasp, there may be no nest to worry about. However, multiple wasps, repeated activity, or sounds coming from the walls deserve more attention. Avoid disturbing a suspected nest, since this could provoke the insects. If you are uncomfortable investigating the area, a pest-control professional can safely determine whether a nest is present.

To reduce the chances of wasps entering your home, seal cracks and gaps around windows, doors, vents, and utility openings. Repair damaged screens and make sure doors and windows close tightly. Keeping outdoor areas free of food debris and removing potential nesting spots can also help prevent future problems.