i live in the upper midwest and winter 300 colonies, some 2 deeps and some singles. 

the 2 deep colonies get pushed together into a 4 pack on a pallet. each colony gets a built rite fiber 
insulation board over the inner cover then a sheet of black poly or tarpaper over the top and sides 
leaving the 2 front sides of the 4 pack exposed. the other important feature is having two openings 
to vent condensation top and bottom. 

for stacked singles we remove the inner cover from the bottom deep and install a screened spacer 
board between the two and then wrap as described above. 

i don't worry much about insualtion as i have 6 frames of bees minimum in each and combine any 
weak ones. single deeps that are not stacked i do place on foam insulation boards and wrap in 4 
packs. 

the other big factor is location, location, location.  higher ground with good air ventilation facing 
south with a wind break from the NW is what i look for in a winter yard. 

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