A tbh body must be large enough for both the bees and the beekeeper’s needs. And it’s shape can enhance colony function:
- taller hives can overwinter better
- shorter hives can dissipate interior heat faster
- shorter hives permit harvesting honey from more frequent, less intense nectar flows
Beyond a tbh’s shape, additional functionality can be built:
- to use standard Langstroth frames
- with sloped or straight side walls
- to provide an end space
- with legs providing a comfortable working height
- with multiple entrance locations
- to use lifting cleats
Bees are adaptable creatures with minimal shelter requirements. Temperate climate bees need a suitable cavity to over winter in. They prefer a cavity with:
- a south facing entrance
- 3 meters to 5 meters above the ground
- at least 25 liters volume
- 40 liters to 60 liters average volume
- a 20 to 40 square centimeter entrance
- an entrance at bottom of cavity
- a 4 centimeter maximum entrance diameter
- subtropical climate bees prefer smaller cavities of 30 liters
- German bees prefer 60 liter cavities
- Africanized honeybees prefer smaller cavities of 22 liters
- in the hottest areas bees often forsake a cavity for a nest in an open, shady, sheltered place
Mark Winston’s “The Biology of the Honey Bee” and Tom Seeley’s “The Wisdom of the Hive” are two great books to read about the bee’s needs.
Beyond what the bee’s need, extra space allows more flexibility for hive management. It:
- decreases the need for frequent inspections
- provides a convenient space to feed or split a nucleus
- makes a hive easier to work
- and can be reduced using a follower board
Cavity shape is also important. In a temperate climate, with a few, intense nectar flows, taller comb and a shorter hive length works better. The bees can backfill a larger broodnest before storing surplus honey. That insures the best possible conditions for survival during a bad season. And the cluster is in a more compact shape resulting in better over wintering.
In warmer locales, with more frequent but less intense flows, a longer top bar hive with a shorter combs is more functional. The shorter combs allow the beekeeper to harvest surplus honey, which might be inaccessible if stored only in taller broodnest combs. A cluster is a long, shallow box would have more surface area which might be easier to cool during the hottest times of the year.
If a beekeeper runs conventional hives along with tbhs, a hive that can fit standard frames beneath a top bar is useful. This allows a standard frame to be fastened to a top bar. Then the entire frame can be removed or eventually incorporated into the natural comb structure.
Or a hive can be designed so standard frames set in place of a top bar. That converts a top bar hive into a long hive. Since frames are self spacing, gaps will be left between the frames and adjacent top bars. A cloth inner cover is used in such a case.
It was thought that sloped sides reduced comb attachments. I’ve experimented with different slopes and found no difference. The bees will attach comb to a sidewall when more support is needed. Sloped sides are aesthetic. But they add more complexity to the construction, especially for someone with limited tools or wood working experience.
Additional space is needed between the end combs and the tbh. Without it, the bees attach the end combs to the hive body making them difficult to remove. Usually 1/4″ to 3/8″ will suffice.
Some beekeepers manually provide that space and use it as an upper entrance.
A spacer cleat can be fastened along the top edge of each end to provide the proper clearance. It’s easy to alter a top bar for this purpose. And a removable spacer cleat provides access to the back side of the last comb when all top bars have comb.
Tbhs can have legs which:
- raise the hive to a comfortable working height
- place the entrance above grass and pests
- make a fantastic looking honey cow
But honey cows are:
- difficult to move
- are tall and top-heavy
- a hand cart is useless
- can’t be stacked
Removable legs can be used. But they require much more effort and time. And removing them creates more hive disturbance when it’s best to work fast with as little disturbance as possible.
Hive stands are another way to get most of the benefits of legs without all the hassles. I consider them an accessory and write about them there.
Bees have entrance preferences. But they are flexible regarding a hive entrance. Bees will select a cavity with the proper size and shape. Then they work with whatever kind of entrance it has.
Beekeepers build tbhs with entrances:
- in an end
- at the bottom between bottom boards
- at the top by removing a top bar and raising the cover
- along a side
End entrances work great for migratory beekeepers. And when hives radiate out from a central working space.
A bottom entrance works great on a tbh with legs. The entrance is above the grass. Drains freely. And can incorporate a bottom screen.
A top entrance is a great solution for a legless tbh. It gets the entrance away from grass and pests, especially skunks. If facilitates supering.
Side entrances are great when hives placed along a wall or in rows.
When given a choice, my thb bees preferred a side entrance at the bottom edge of the hive body. Such an entrance provides more ventilation and a shorter travel path than an end entrance. If used with sloped sides, a side entrance is suitable for a migratory operation.
During winter, a side entrance, when faced south, exposes the long side of the hive to more direct solar energy than other entrance configurations.
Just how does a person adjust the position of a heavy, legless top bar hive? Lifting cleats are a neat solution. They can be staggered to give air space, yet allow tight stacking for a migratory beekeeper.
Without them, it’s like wrestling a large pig that bites. 🙂
A vertical tbh? I’ve got my own vertical tbh design.
And check out the Warre’ hive. These have some interesting natural beekeeping possibilities.