Let’s put a few myths about condensation and ventilation to rest…
Q. What causes condensation?
A. High humidity air coming into contact with a cooler surface.
This is caused by the air temperature inside the hive being warmer than the surface temperature of the hive walls and roof.
Ok, how do we prevent it?
- Warm up the hive walls and roof to nearer the temperature of the internal air.
- Cool down the internal air to nearer the temperature of the walls and roof.
You do (1) by insulating the roof and closing off top ventilation.
You do (2) by adding top ventilation.
Both work to reduce condensation, but (1) results in a higher average internal hive temperature than (2).
For proper development of the brood, the bees need to keep the nest at a temperature between 32C and 35C.
Brood development may be total of a day or so shorter with warmer hive temperatures.
The slightly shorter cell occupation time for a developing bee has benefits for both decreasing varroa mite population AND increasing worker bee population, the female varroa not being able to produce as many offspring for each generation during the shorter capped pupal phase of the bee, and the bees having a quicker turnover of brood cells with the shorter development time. Bees raised in a warmer hive are also healthier and live longer.
(If a worker bee life is increased by just one day, then that’s a 2% increase in the work able to be done.)
The numbers might be low percentages in each case, but the advantages are exponential over a season and are there to be taken.