Bee's Needs

Bees are very adaptable creatures with minimal shelter requirements. Temperate climate bees need a suitable cavity to over winter in. Few would survive if exposed to the elements. They prefer a nest cavity with the following attributes:

• a south facing entrance.
• 3 to 5 meters above the ground.
• at least 25 liter volume.
• average 40 to 60 liter volume.
• 20 to 40 square centimeter entrance.
• entrance at bottom of cavity.
• 4 centimeter maximum entrance diameter.

Subtropical climate bees prefer smaller cavities of 30 liters. Bees in these climates often eschew cavities and nest out in the open. And they often migrate as conditions or seasons change.

Different races prefer different volumes. German bees prefer 60 liters. Africanized honeybees prefer smaller cavities of 22 liters.

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.

Beekeeper's Needs

Beyond what the bees need, a top bar hive must meet a beekeepers needs. Some things to consider before designing a top bar hive:

• purpose.
• skills/tools.
• construction materials.
• migratory.
• management style.
• scale of operation.

A migratory, extensively managed, large scale, commercial beekeeper would value compatibility, stack ability, portability, optimum conventional material use, and enough volume for maximum flexibility in a top bar hive design.

An organic gardener, needing a few hives for pollination, might value appearance and workability.

So, the first step in top bar hive design is to prioritize a list of the bees needs. Then second, the beekeeper's needs. Keep your list handy and compare any top bar hive design to it. There's no single top bar hive design that is optimum for all bees, climates or beekeeper's needs. And since you have to build one for yourself, build the best one for your bees, climate and needs.

Hive Body

Cavity Volume

The hive body is just a trough shaped box. Since a top bar hive is self contained, it must be big enough for both the bee's and the beekeeper's needs. Bees will only need and occupy so much volume. Extra space beyond the bees needs provides additional flexibility. It decreases the need for frequent inspections. Provides a convenient space to feed or split a nucleus. And makes a hive easier to work.

Cavity Shape

The shape of the cavity is also important. In a temperate climate, with a few very 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.

Sloped Sides

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 additional support is needed. Sloped sides are very esthetic. But they add additional complexity to the construction, especially for someone with limited tools or wood working experience.

Legs

Top bar hives 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. They are tall and top heavy. A handcart is useless. They 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.

Entrance

Bees have entrance preferences. But they are very 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 top bar hives 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 outward from a central working space.

A bottom entrance works great on a top bar hive 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 top bar hive. It gets the entrance away from grass and pests. If facilitates supering. And requires no modification to the hive body.

Side entrances are great when hives are placed along a wall or in rows.

When given a choice, my thb bees preferred a side entrance located 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.

Top Bars

Width

Top bar width is controlled by comb spacing. A proper width allows a single comb to reside on just one top bar which enhances its removal. The wrinkle? Bees build different types of comb at different comb spacings. In the broodnest, comb is spaced at 1 1/4". Comb spacing increases as the broodnest transitions into the honey storage area. It's often spaced up to 2" there.

Some use a single broodnest width top bar throughout the hive. Overlapping honey storage combs are cut or moved as a unit, without separating individual top bars. Then they are harvested when ripe.

Others use a slightly wider top bars at 1 3/8". It's not optimal for the broodnest. But it's accepted in the broodnest area and works for more comb in transition to the honey storage area.

Using several different top bar widths is a common solution. They vary from 1 1/4" in the broodnest, to 1 3/8" in the transition area, to 1 1/2" or more in the honey storage area.

Another solution involves optimizing the top bar width for the broodnest at 1 1/4". Then using spacers that are inserted between top bars when additional width is needed.

Rigidity

Since top bar hive comb is attached and primarily supported by the top bar, it's imperative that the top bar remain rigid. Any top bar flexure will cause comb failure. Rigidity is a function of top bar length and thickness. To maintain rigidity, longer top bars need to be thicker.

Taller, heavier comb requires a thicker top bar.

Migratory top bar hives are subjected to the rigors of stacking, rough roads and handling. They require a thicker top bar.

Will the beekeeper set on the top bar hive? Will it be top supered? These situations require a thicker top bar.

Comb Guides

Most beekeepers use some method to center comb building down the length of a top bar. All work some of the time. Some work most of the time. But none work all of the time.

• dribbled beeswax ridge.
• beeswax filled saw kerf.
• foundation starter strip.
• wooden spline.
• milled ridge.

Fixing beeswax based starter strips in a saw kerf with melted beeswax is problematic. If the wax is too cool the strips will fall out at hive temperatures. If it's too hot, the lower portion of the strip will melt. That results in a starter strip resting on a beeswax filled kerf. These are very weak and easily break off. Using plastic foundation strips rather than beeswax negates this problem.

Reinforcements

Top bar comb is fragile. It's particularly weak to rotational forces applied perpendicular to the comb. Top bar hive comb can be significantly reinforced by incorporating vertical supports which extend downward from the top bar. Bees incorporate these reinforcements into the comb as they build the broodnest.

Reinforcements have a few disadvantages.

• complicate top bar construction
• are fragile and warp when stored
• hives and reinforcements must be absolutely vertical during comb building
• bees sometimes build around them
• frustrate comb cutting/honey harvesting

Cover

A cover protects the top bars from the weather. It drains precipitation. Provides shade and ventilation when it's hot. And insulation when it's cold.

Most top bar hive covers are lightweight with a large surface area. So, some means should be incorporated to keep them from blowing away.

A sloped cover provides good drainage and ventilation. It compliment the looks of a top bar hive with sloped sides. But they take a more time to build and are harder to insulate. They don't stack at all, an important factor if you move your top bar hives.

A flat cover is easy to build, insulate, and the covers are stackable. When propped up, they provide shade and ventilation. But they are ugly and have marginal drainage. If you live in a wet climate, be sure to build a flat cover using suitable material. Or give it a proper waterproofing treatment. Without such, a large, painted, poorly prepared, flat cover has a short life.

Accessories

Follower Board

A follower board is used to partition a top bar hive. It's the same size as an end piece. With it, a queen can be raised or a nuc run in a hive's far end.

Some beekeepers use a follower board to reduce the hive volume. Then they gradually increase the volume as the colony grows. It's reported that this helps the bees draw out straighter comb.

Lifting Cleats

Just how does a person adjust the position of a heavy, legless top bar hive? Lifting cleats provide a neat solution. They can be staggered to provide air space, yet allow tight stacking for a migratory beekeeper.

Top Bar Stand

A top bar stand is an essential piece of equipment, as most top bar comb must be held, in it's natural position, with both hands. A simple wooden frame, slightly larger than the comb can be used. Some beekeepers extend a top bar hives sides beyond the end pieces. That provide a place to hang top bar combs.

Feeders

A quail type dribble feeder is commonly used to feed sugar syrup inside a top bar hive. Feeders can also be incorporated into a follower board. Plastic 2 liter pop bottles can also be used to feed bees much as they are with standard equipment. Except the access holes are drilled through a few special width top bars rather than the hive cover.