All over the internet it’s possible to find anecdotes about prime swarms in Warré hives taking “only a couple of weeks to build three boxes of comb”, but it isn’t always the case. My four week old swarm is currently enjoying all the space of three boxes, but have only built in the top box, even with the epic weather we’ve been having.
What to think, what to do! Firstly, the bees appear to be fine. They’re busy, there’s pollen coming in, there are orientation flights going on, the hive entrance smells of honey when the bees are fanning, the bees are well behaved.
I know that I can take off one of the empty boxes, put some wax ladders onto one of the bars and put it on top of the current top box, i.e. super it. The ladders will encourage the bees to fill the empty space above them, and probably stress them out quite a lot. I could also put ladders into box two to encourage them to build down, but they know the space is there; they’ll build when they’re ready. I hope!
Should I be concerned about the building being only in one box? Can they survive winter on one box? Probably.