Overwintering (again)

Ok - now that I have decided for an outdoor hive in USDA Zone 6a…

Some questions/commentary about temperatures/insulation/ventilation…

  1. In most ways, the concepts behind hive protection should be similar to house protection. There is warm, moist air inside and cold dry air outside. We want to stay warm and dry without condensation on our windows but with an indoor RH% of 35-45 (lower if the insulation is poor). Do we need to reinvent the wheel?
  2. We accomplish this by making the building tight and well insulated, maximizing thermal mass, and ventilating as needed.
  3. In a modern house, we have well insulated walls, windows, attic floor, with a cold, ventilated space under a gable roof. There are moisture barriers on the walls but not the attic floor, at least not here in Ohio.

So, how to accomplish in a hive?

  • Convective, passive ventilation from bottom to top
  • Insulation with vapor barrier on walls (in my house (from outside in), siding- Tyvec house wrap (which is partially vapor permeable)-sheathing-insulation-vapor barrier-drywall-paint
  • Ventilated gable roof with permeable insulation
  • What about thermal mass? Can you increase the thermal mass (and reduce extreme temperature fluctuation (winter and summer) of the hive with phase change thermal pads (ie bags of water or those disposable ice packs that you get in the mail and that I have a whole freezer full of).

So, the hive could be (from outside in):
Water resistant but vapor permeable fabric (canvas, sunbrella fabric)
Tyvec
Foam board insulation
Water bags
Lastly, the box.

The top (from outside in):
Ventilated gable roof
High-R insulation (of your choice, natural wool, wood chips, mineral wool, fiberglass, cellulose, etc.)
Screened, ventilated inner cover

The only heat supply is the cluster.

DISCUSS!