Derekm, I can see the logic behind your open floor design, but I’m wondering why you didn’t go with a more conventional insulation approach? Why did you choose to go with an open floor and a closed top instead of a more conventional small bottom vent/entrance and a small top vent/entrance? What are the advantages and disadvantages?
I understand your use of mesh and grills to try to create a dead air space (insulation) in the floor area of your hive. Where I live we get a lot of wind in the winter and have to confess I would worry about wind washing the heat from the hive as Finski fears. However I’ve never tried it.
I also worry about the exchange of gasses (CO2, O2, and water vapor) with a closed top. I’ve stuck with a conventional insulation design like Finski, but am always interested to hear how other approaches work. I’m not enough of a rebel myself :(, but like to watch the rebels at work :)
You gotta get us a photo of this hive!!! I’m very curious to see it.
finski - those pictures are of a nuc (half size) hive, it takes 5 British national frames.
As regards knowing about air movement and insulation several years i worked for the UK subsidary of Svenska Flaktfabriken (Flakt).
blue bee: the full size hive is just twice the width. internal dimensions are just british national. Though next year they will be extended to 14x12.
Inside the hive there is good air circulation provided by the heat of the bees and the cooling of the wall. Cold air and Co2 will fall to the grid Co2 will tend to fall faster, further, the the higher humidity air will be denser and so there will be low velocity interchange with air below the first grid (floor). The small gaps in the second grid again 3mm prevents high air velocities in the below floor plenum chamber.
There is no wind washing near the floor, the wind is baffled by the deep sides and bottom grid, and to really sure there is the vermin mesh under the second grid (12mm mesh).
In winter survival, in a snow cave you build a ledge with a pit alongside and sleep on the ledge. the cold and and CO2 accumate in the pit. my hives have a grid so the Co2 and cold air can keep falling.