Flat crown board with 1.8 cm rim and ventilation

01 · WHEN IT IS THIS ONE

A low rim: it closes without gaining height

The 1.8 cm rim leaves just 4 mm of clearance above the frame top bars — enough to respect the bee space so they do not fill it with propolis and glue the board to the comb. If your outer roof already has depth of its own — a deep roof, a telescopic one, one with an air gap — adding a tall eke underneath only piles on weight and bulk for nothing. That said: if what you need is internal space for a syrup bag or a crown-board feeder, this is not it; you want the 4 cm eke version.

02 · THE VENT

A mesh disc that does three jobs

In the middle sits a plastic disc with mesh and a tab, and it gives three different uses depending on how you leave it. Open with the mesh in place, it ventilates on hot days or during short moves without letting a single bee out. Uncovered, it is the port to stand a rapid feeder over when you occasionally need one. And half open through winter, it lets out the moisture rising off the cluster, which is the real winter enemy — not so much the cold as condensation dripping back onto the bees.

03 · HOW IT IS MADE

Smooth hardboard and a solid rim: that is why it lasts and why it weighs

The base is hardboard, a pressed fibre panel that is stable against the damp inside a hive and smooth-faced: it leaves no gaps for the bees to fill with propolis. The rim on all four edges is solid pine, and that is the part that takes the weight of a loaded roof and the leverage of the hive tool prising it off. Hence the trade-off worth knowing before you buy: it is a solid, insulating crown board, and that is why it weighs more than a thin sheet. In migratory work, where every gram is multiplied by the number of hives, some beekeepers prefer something lighter. And if you drill it for another use, go slowly with a backing board behind: hardboard blows out when the bit exits at speed.

04 · BEFORE YOU BUY

It comes in the two standard market sizes, and you choose by your hive body: 510 × 425 mm for Langstroth and Dadant US — one size serves both — and 500 × 425 mm for Dadant Blatt, the French measure. There is no Layens version: that format has a different body size and needs its own crown board.