I have heard that ventilating the top of the hive is very important, but have read lots of different methods for doing this.
- Upper Entrance hole cut in top super
- Raising the top cover or inner cover by sticking something to prop it open - stick, bottle cap, sofa tack, etc...
And please indicate whether you are ventilating over winter as well as in the summer.
At spring, when night are cold, it is good if ventilation is only through main entry. But if bees do the cleaning fliht through upper hole, you cannot close it any more. But you can do it almost littel finger size. If hive is too ventilated, chalk brood may attach easily.
I use "Upper Entrance hole" during summer in every two box. Every box is too much.
Bees ove to fly through holes, but first of all, holes are for biggest honey flow ventilation. I deminish the main entrance if weather demands it.
I never lift the ceiling for ventilation. My hives are 150 km from me and I cannot run every time to help them. They must care themself whole week or a month.
I use the lowest box as a porch. Entrance is wide and ventilation is free.
At winter the main entrance must be guite widden. Also it must be finger tip size upper hole, taht moisture comes out.
If you have grid bottom, then upper holes are closed.
Our winter last 5 -6 months that they cannot come out.