Hi Michelle, I like a solid floor because I believe the bees only need an entrance. With a proper entrance they are able circulate air throughout the hive. All they have in the wild is entrances, if the entrance is too big, the bees will block some off with propolis. I’m not a fan of tiny entrances either.
You’ll see the odd photo in books & on videos how bees circulate air throughout the hive. One example is tissue paper on one side of the entrance being sucked in at the same time tissue paper on the other side being blown out. This is why I like an entrance with a bit of width about it. So that the air coming in doesn’t clash with the air being blown out.
I have a friend who made a long Lang hive. He made a beautiful job of it. However he wasn’t impressed, admittedly he didn’t trial it very long. He believed bees in his normal Lang hive performed better.
Another thing about a long Lang hive is: it’s heavy & cumbersome to move around compared to normal Lang hives that can be separated.
If I was going to build a long Lang hive, I’d have one wide entrance & no screen bottom board.
Having said all that, I believe people use SBB’s as a form of mite control. Something we don’t have in Australia yet.