Two identical colonies are shown side by side: the left hive is kept on a single Langstroth deep brood box (10 frames), the right hive on two stacked deep boxes (20 frames). Both hold the exact same population slider value — only the amount of comb space available to that population differs. Everything else in the simulation (comb congestion, queen-cell formation, honey stores and winter survival) is derived purely from how tightly the same number of bees is packed into the available frames.
A single deep box gives a beekeeper a lighter, faster, cheaper-to-inspect hive with less risk of missing a queen cell buried in a second storey — but it hits its comb-space ceiling sooner, raising swarm risk during a strong spring flow and leaving less room to bank the honey stores a colony needs to survive winter. A double box roughly doubles both the safety margin and the inspection time. Neither configuration is "correct" — it is a trade-off between swarm control, wintering security, honey yield and the beekeeper's own time and back.
Two identical colonies, one on a single deep brood box and one on two stacked boxes, are shown side by side so you can watch how comb space alone changes congestion, swarm-cell risk, honey stores and winter survival odds.
The same population is applied to both hives at once. Occupancy, queen-cell formation, honey stores and winter stores runway are all computed from how full the available frames are — the single box hits its ceiling at roughly half the population the double box can absorb.
Drag the population slider and change the season to watch the comb heatmap, swarm-cell overlay and winter cluster respond on both hives simultaneously, then compare the dashboard numbers underneath.
Congestion, not population alone, is what triggers the swarm impulse — a colony that would be comfortable in a double box can feel dangerously overcrowded in a single one during a strong spring nectar flow.