condensation in hard frost -20C

[Oandy]

Hi Rab the varroa board is plastic with a upstand at rear and are sited level. As you say i remove board now and again to clean. I have not seen pools or drops of water on the boards when ever i have cleaned the boards as hives are only 2ft from my house wall they do get good protection from driving rain/snow. I have one hive out of the six with a differant board. Which shows small drops of water now and again. As i work in damp proofing i may check how much humidity is in the hives when the water drops are visable on the single board and when no water drops. I also have one hive with the bee keepers happy floor which has no varroa board. so i placed heavy black plastic sheet between stand and floor, while i was treating with Thymol oasis board. Andy

You may have to describe the varroa inspection board design a tad. Does yours have an upstand at the rear? Pulling it out leaves a gap at the front and rear? What stops water getting onto the varroa check board; do you slope the hive so it runs off? Do you remove it at intervals to remove detritus?

Lifting the brood box 3-4mm is enough ventilation, even with a solid floor and no top ventilation, I have found (but need to take precautions to avoid water collecting in the hive if using a solid floor)

RAB