I think you have a typo in the 3rd paragraph when you describe building a Styrofoam hive out of 40cm thick sheets! That would be massively thick. Guessing you meant 40mm.
Yes, I spotted that typo after uploading it.
50cm are pretty deep brood boxes indeed! My jumbos are about 38cm deep and have a brood box cell capacity of 120,000 cells. That is a LOT of capacity, probably more than most queens can lay. A little math suggests there isnít much purpose in going beyond 120,000 cells for a brood area.
* Are they 50 cm deep? They're supposed to be 37 cm deep (and the short-deep has two of them, totalling 70 cm).
* Also don't forget that these are Dutch simplex frames (same as British National frames), of which the comb is only 33.5 cm wide. A Langstroth frame is 43 cm wide, isn't it?
* Are you sure your jumbos are 38 cm deep? Aren't they 28 cm deep? I'm just asking -- I have no idea what kind of a hive you have.
Hmm, if your brood box is 120 000 cells large, then that means 7 of my large frames will have the same capacity as your brood box. [We use 5.2 mm cells, i.e. 55 cells per sq in, i.e. 85000 cells per m2.] Well, there's no need for me to use 12 frames per box -- local beekeepers often use 9 frames in a 10-frame box (the 10th "frame" is a spacer that you take out when you do hive inspections, so after each full inspection the spacer is on the other side of the box).
Bottom line; I donít think youíre going to need two brood boxes when each brood box is a whooping 50cm deep.
That sounds like good news.
You also mention going with bottom bee space because it is easier to build. I agree itís easier to build and Iíve done itÖ..and regretted it.
Well, yes, it is easier to build, but local beekeepers also use bottom bee space on most of their hives, so if I want my hive bodies to be interchangeable with theirs, then bottom bee space would make additional sense. What did you not like about bottom bee space?