I see what you are saying. But isn’t a 8 frame medium the same volume as a 5 frame deep?In my mind, a single 8 frame medium is not a nuc, it is a too small hive. If you are running medium frames, use two 5 frame medium boxes for the nucleus colony. I winter my nucs in single deeps, 5 frames with a feeder on top, but have built the double mediums for a friend.
I use 10 frame equipment, but accidentally acquired 5 or so 8 frame boxes when I was getting started 3 yrs ago. All medium. I use the 8 frame boxes for nucs, and overwintered one last year using a shim and sugar brick. It did ok and quickly grew to packed status and would have been easy to let swarm. Just got to keep an eye on the population, they can quickly grow too packed.I’m in Georgia and I’m thinking about doing a split of my strongest hive and try to overwinter some nucs in 8 frame mediums. Anyone had success at this? Tips?