I was going to use commercial insulation but an old beekeeper gave me a good insulation tip last year.  He said to place a newspaper or two over the inner cover.  So, for this past winter, I placed a small piece of #8 screen over the inner hole (to keep the bees from getting at the newspaper) and put a 1/4"(~6,35mm) thick stick that reached from the inner cover hole to its edge (a ventilation channel).  Then, I put 2 newspapers over thus prepared inner cover and replaced the outer cover.  It took 2 minutes per hive.

I checked the hives on nice days this winter.  As I was removing the newspapers, I felt warmth between the inner cover and the newspapers (they make good insulators).  The bottom of the inner covers was very dry and free of mold (the newspapers absorbed excess moisture from the hives).  The clusters appeared to be well-dispositioned (stress-free).

I might add that the local newspaper here is Newsday and it's about 1/2" thick.  Two Newsdays, laid side by side, fit nicely over the inner covers.

Waldemar
Long Island, NY

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>>With regard to the top isolation set up and low
entrance ventilation, if I understood it well, it
looks very similar to overwintering set up in UK as
far as only the top box is considered. Am I mistaken ?

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