There's not been many around this year, fortunately.
However, today I went into the summerhouse to get some cushions for the garden bench. The cushions were in a polythene bag which was hanging up. The bag had a small hole in it, and through that I noticed some cardboard inside which I didn't remember putting there. As soon as I took the bag down, a load of wasps flew out. I got out quick as they were very annoyed. The "cardboard" was, or course, a nest they were building. I don't know why they chose the bag as there wasn't a lot of space in it.
I'll wait until evening and then spray insecticide inside the summerhouse.