Here is an update of a previous post: my five favorite ventilation aids for a summer beehive. After experimenting for another year, I have dropped the ventilation eke from my favorites and replaced it with a ventilated gabled roof. The ventilated gabled roof is more efficient in my opinion, and assures a nice dry hive all year long.
When you are setting up a ventilation system, you certainly don’t need to use all five of these suggestions. However, the more you use, the better the ventilation will be. Good airflow lowers the internal humidity of the hive—just what you want since high humidity is unhealthy for bees and detrimental to curing honey. When selecting the method(s) you will use, remember that you want fresh air to come in through the bottom of the hive, and warm, moist air to leave through the top.
- A screened bottom board is a good place to start since most hobby beekeepers install them as a way to reduce Varroa mites. In summer, remove he Varroa drawer so the bees get maximum fresh air through the screen.
- A screened inner cover provides a way for moist air to leave the hive, but keeps out robbing honey bees and predators such as yellow jackets, hornets, and even wax moths. Unlike a regular inner cover, a screened inner cover requires a spacer above the screen so the moist air has a place to go.
- A ventilated gabled roof has ventilation ports on both ends. These openings, tucked just under the peak and screened, allow a horizontal draft of air to cross the top of the hive. This airflow literally pulls the moist air out of the hive. Most houses have similar vents inserted just below the roof peak that do the same thing. I just walked outside and counted six of them in my small house.
- Slatted racks give the bees a place to hang out which reduces the congestion between the frames and thus increases air flow. On hot days the bees hang in beards from the slats instead of jamming up the front entrance and filling in bee space. It is especially effective when used with a screened bottom board.
- Follower boards are also used to reduce congestion in a hive. Anything that reduces congestion increases airflow. Unlike the slatted rack, the follower boards are at the sides of the hive. In my hives with follower boards, the bees used more vertical space for the brood nest. (Since the bees have only eight instead of ten combs per box, they expand into an upper box sooner.) This tall and slender hive structure is more tree-shaped and seems to provide a “chimney effect” that pulls the air through the hive. My hives with follower boards did especially well with honey production.
Of these five items, the first three provide openings for the air to come and go. The last two reduce congestion between the frames so the airflow isn’t restricted by hoards of bees. Used in combination, these items can enhance the health and comfort of your bees and give you a bigger crop of honey.
These are not the only ways to increase ventilation; they are just my favorite. Some folks like to use upper entrances, for example, and some like to use ventilation rims. Do whatever you prefer, but remember to do something.