"Vacutone" wrote in message
s.com...
I just noticed that wasps appear to be nesting insdie a partition wall
here-
..

The question is- can this still go disastrously wrong in some way if I
leave
it there?


Sounds like good cavity wall insulation to me :-)
Don't know about armchair size, but I once had one in a loft that I could
not pull a dustbin bag over when I took it out. The plan was to pull the bag
over it before cutting/breaking it away from the joist to stop bits going
all over the contents of the loft. This was of course after the wasps had
left, I'm not daft enough to try with them in residence.

Mike