Thanks for the reminders, FRAMEshift, och tack för dina råd.
I live about 130 kilometers west of Umeå. That should be enough of a clue for you. :) It's a nice little town to live in but there are no feral or native bees here. No bees at all.
The reason for building top bar hives is that every supplier is quite far away. By thinking like people in poorer countries i still get enough opportunities for beekeeping. I don't aim for anything grand anyway. Just some honey and wax for my little family. If the experience is nice then we have two more locations for bees, but that's way beyond my visions at this time. At first i thought of having just two or three hives, but because of the slightly remote location i'll probably have more eventually to be on the safe side.
I'll try to find some small nordic bees (a.m.m.) but still prepare to regress by rotating out brood comb.
After some searching on the forum almost all of the small tidbits are in place. In one posting i found the size of the top entrance that Michael Bush uses in his TBHs in winter. It's 3/8" or roughly a centimeter. Could the entrance be even smaller? Another post gives the info on insulation. The hives need to have a block of styrene on top of the top bars, but nothing on the sides. I might make the block slightly ridged, though. 3/4" lumber (19 millimeter) will do.
Michaels hive design is simpler than the one I intended to build. There might be minor changes to the original design, though. One would be to adapt to one of the swedish hive standard widths. The A.m.m bees might need different bar sizes too, but i'm hoping they won't.
I guess i can safely start building my hives now.
While writing this post i noticed some words and names getting changed by the forum software. Why does that happen?