When we saw them late summer, we thought they were somewhere close by outside. They were very big and very loud but seemed harmless and we thought they were wood wasps and shooed them out the window, but more kept arriving even with the windows shut.
Then we found the hole on the ceiling and covered it with a cd, but they nibbled round it. Strange as they had a way out through the roof tiles. But it was early November and got cold early and we just waited for the queens to fly away and the rest of the nest to die out naturally. We were too scared to go in the attic, where the access in this part was on hands and knees and be faced with cornered, angry hornets