Our balcony is primo A-1 super+++ wasp habitat. They love it. They adore it. They advertise it in little waspy magazines with phrases like "must see" and "build to suit" and entirely too many exclamation points.
Monday, I went out and knocked down five (5! FIVE!) different proto-nests. Today, only one, but I shall remain ever-vigilant. The balcony belongs to ME, dammit, not to nasty stripy insects that mock my paper-mache skills.
We have a Spray Can of Instant Death That Should Never Ever Touch Anything That Might Once Have Been Near or Thought About a Water Supply (we got the less toxic kind, see...), but so far I've caught them early enough that the patented half-pitcher of soapy water plus long-handled death from a broom method has been sufficient.