Bottom board question

[CoolBees]

I've noticed that bottom boards come with 2 different spacings. 1 is "taller", and 1 is "shorter". Every picture I see shows the "tall" side being up - towards the hive for the entrance, and the "short" side being down. My screened bottom boards (which are not "reversable") have the tall spacing also.

However, as I watch returning field bees entering the hive, I've noticed that they have a hard time climbing up into the frames with the taller spacing. Most of them walk all the way to the back of the hive and climb the back wall. Or they climb the sides. With an entrance reducer on, they will climb it.

I've also noticed that they make several attempts to reach up and grab other bees to lift themselves up into the frames, as they march towards the back. Sometimes they are successful, but mostly not.

So I flipped a couple of bottom boards to the "short" side. In these hives, as the bees land and march in, they climb directly into the frames anywhere they choose without effort. The entrance is far less conjested this way. It seemed to eliminate the massive traffic jam at the entrance that occurs on a busy day as the bees all look for a way to climb up.

So my question is, what is the reasoning behind the height spacing of the bottom boards? Why are there 2 different thicknesses? Is there a "right" and a "wrong" side of the BB? If so, why?

Thoughts and comments appreciated. Thanks.

[Michael Bush]

The original plan for "reversible bottom boards" was to put the deep side up during winter with the entrance reducer in with the opening up so that if dead bees accumulate the bees can still get out.  That seems to have fallen into disuse.  Now it seems most people just leave it with the deep side up all year and if they use a reducer they put the entrance down.

[blackforest beekeeper]

Hey Alan,
my hives got "basements" from 3 to 5 inches. This I did so the bees could hang out in there. Esp. during transport (I lost hives due to not enough room and air during transport). I use one brood-box only (corresponding to 11 deep frames, but I have used less with a follower board). No disadvantages in this, I would say.
These days I use a forklift for moving hives and the entrances stay open during transport. This way they can just come out and beard if they get too hot on the trailer. So I make all new bottom "boards" (they are pallets, screened) appr. 3.5 inches high, the entrance slit (just a bee space high) is in the middle of that between screen and frames.

[CoolBees]

Mr Bush, thank you for the answer. It all makes sense now. I feel like Master Ragettie in the 3rd Pirates of the Caribbean, as they are transiting the antarctic, shivering with cold, and he says, "I-I k-knew there m-must be a r-r-reason!" 

Blackforest - your ideas make sense. Your leaving space under the brood nest for clustering, similar to what Slatted Rack does - if I understand such things correctly.

[Michael Bush]

The slatted rack has the added advantage of preventing them from building comb off the bottom of the frames down into that space.

[CoolBees]

The slatted rack has the added advantage of preventing them from building comb off the bottom of the frames down into that space.

I hadn't reached that question yet, but I would have. Thank you for answering it. That explains why I've read that's it's critical for the slatted rack and frames to line up, also. The slatted rack is "cluster room" without "comb building" vs just empty space for clustering.

Thank you Sir.

[blackforest beekeeper]

Some of my bottoms got slatted racks, just thin strips of wood one beespace under the frames.
As for the most part they do not build downwards (I did have some severe problems when I got different frame sizes in the boxes....), I did not build any for the new hives. But I got jumbo-frames, which are 2 inches "deeper" than a deep.
They need enough room for drone-brood, otherwise they build them where they can.
Sometimes they build downwards anyway, but only during or before swarm-season. I remove that comb. From mid-May on I don`t usually worry about the brood-chamber any more, so if they still build a little, I don`t care.
It IS a nuisance, "wild" comb where we beeks don`t want it.

I did one thing with a similar frame and box size as a deep: No drone-frame. So they just fill up the bottom with drone brood. I tilted the box about twice in swarm-season, smoked them and removed it. That was to control varroa, too. I don`t remove drone-brood any more and the jumbos probabyl give them a sense of enough area for a brood-nest. Scraping off underneath always has the danger of killing a queen. But I know that some rather large apiaries (for Germany the largest has 8000 hives) do just this. They run 1 single deep for brood. If you are well "suited", this is fast work and you can see if they built swarm-cells right away. AND you don`t have drone-comb in the hives during summer asf.

[Michael Bush]

>I hadn't reached that question yet, but I would have. Thank you for answering it. That explains why I've read that's it's critical for the slatted rack and frames to line up, also. The slatted rack is "cluster room" without "comb building" vs just empty space for clustering.

They don't need to line up and in fact a traditional slatted rack the slats go 90 degrees from the frames.  The idea of lining them up came because of screened bottom boards and people wanted the mites to not hit the slats when they fall through.  Most of my slatted racks over the years are 90 degrees from the bottom and I prefer these.  The idea was to baffle the air coming in so as to prevent drafts while allowing ventilation.