Re: 3 Foot Long TBH---Have you tried it?
It's cool folks, I got this
I am currently in the process of constructing a 4' hive because my 3' has been outgrown. I posted about it a week or so ago, asking how to do a successful transfer once I have it built. Now as Bush_84 stated, the volume is what really matters. I somewhat double screwed myself with the 3' TBH. What I did extra was cut the hive down in height, so instead of an 11" ceiling, I took it down to about 9". I did this out of fear that the combs would get too heavy and collapse when it gets up to 110 degrees this summer. Doesn't matter, I had one collapse the other day anyway, after doing a general hive inspection.
Anyway, I'd recommend the 4' hive with the movable back wall. I used the leader board like this to keep my girls cozy when I first installed them. Each week, I open the hive and move the leader board back a few spaces, adding bars into the brood nest as I went. That is what was meant by "opening up the brood nest". The new bars are pulled with comb rapidly, and just as quickly as the comb is built, the queen has laid it.
As it stands, I have moved the leader board as far as I can, actually removed it altogether. Looking the hive last night, I observed comb being built on the second to last bar, and it has capped brood on it. So it seems that I have a 3' brood nest, with no bars of pure honeycomb to speak of. I'm hoping that when I transfer then to the 4' hive, the extra space will finally allow them to start storing up honey. If they fill that one with brood too, I guess I'll have to try my hand at a 5' hive (mentioned above as not a good idea) or find a way to add a super on top of the hive.
For future reference, I do not recommend a 3' TBH. I will always build 4' minimum, or 42" as another suggested, and just use the leader board as a false back wall. This way you can, in effect, have as small of a hive as you want, but should always have room to grow.
One package to 4 hives in 3 months. After 12 months I'm over a dozen hives and growing. Head over heels for bees!!!