How Do I Keep the Hive Ventilated in Winter?
Ask the Expert!
Tara of Denver asks:
I was just curious as to what you use to prop up the hive roof for the winter. I’m new at this, from what I’m reading, as long as the roof is propped up and the middle of the roof hole is open, that should be enough ventilation.
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Rusty Burlew replies:
How much ventilation you need in a hive depends on many factors, including your local climate, the size of your colony, your wind exposure, and your sun exposure. Although I can’t picture the specific configuration you are asking about, as a general rule, I don’t think lifting the lid with a shim is a good solution to ventilation.
Usually, when you prop the lid with a shim, you get an opening across the front of the hive plus openings along each side that get smaller as you move toward the back. To visualize, lay a book on your desk, and put an eraser under one end. Although the opening isn’t wide, it has a lot of area. Not only can this area admit wind and blowing rain, it can also welcome pests — spiders, slugs, other insects, and even mice and voles.
I much prefer a ventilation hole of about 1-inch in diameter drilled into the top corner of the upper brood box. Alternatively, you can use an Imirie shim, which has an upper entrance of about 3/8- by 5/8-inch that works fine for ventilation. These entrances are small enough to let warm air out without letting everything else in. When I use one-inch holes, I cover them on the inside with screen or hardware cloth to keep out the wintertime visitors.
If you see moisture condensing under the roof, you probably need a bit more ventilation, but if you see no condensation, you may already have enough ventilation. Each colony is an individual, so it’s impossible to make a recommendation that works for all of them.