Jorn Johanssen says he has successfully overwintered in Styrofoam
(polystyrene)
hives in Denmark and reports beekeepers doing so in British Columbia,
Canada.  (He does not address whether upper ventilation is provided).

My own hives are tight and without upper ventilation. But I use open mesh
bottom boards.
I place a sheet of clear plastic under the lid, and the bees glue it fest
with propolis all way round, so there is no upper entrance at all. I have no
problems with condensed water in those hives.

The nuchs is placed on top of strong hives as you will place a super, but
there will be this sheet of plastic between the strong family and the three
queen nuch box. This box is also covered with a sheet of clear plastic, and
the bees in the nuc's also glue al the way round. The lid is isolated with a
30mm styropor plate. The supers I have is 30mm Styrofoam in wall thickness.
I am using no additional isolation, because it is ok for us here. Styrofoam
is a high class isolator.

For information. One langstoth box with wooden frames and foundation 10
pieces is 4.5kg

the Canadian beekeeper showed us the over wintering bee yard. His boxes are
about 30mm thick and tight. there are no open mesh button bard because he
use the bottom to feed  through the entrance. on one of The pictures
http://apimo.dk/programs/canada.zip or http://apimo.dk/programs/canada.exe I
put on the server shows a pile of covers with mesh but those are for
wandering, not for stationary use. He is what I will call a big beekeeper,
several thousand families (five thousand if I recall right). and the
beekeeper family developed those nuc Styrofoam boxes themselves. Each nuc is
feeded with 3kg sucker in autumn and 2 kg sucker in spring. he use one
varroastrip a nuc, and I recall he also mentioned it was needed to give
medicine against nosema.

best regards

Jorn Johanesson

EDBi = Multilingual software for beekeeping since 1997

home page = HTTP:\\apimo.dk
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