I have recently built a top bar hive.  The recent cold snap has made me
re-evaluate its effectiveness in cold weather.  Since it has legs, cold air
can circulate under the hive as oppose to the dead space under conventional
hives.  The single layer of frames would seems to be less effective in
holding heat.
 
Should I expect higher winter mortality with this type of hive?  Is winter
insulation appropriate.
 
Charles Henry
Little Rock