Hi Frank

There are two distinct issues involved here...

1, how big should a bee space be?

2, Should this space be at the top of the box or should it be under the
frames?
 There is an additional rider here that the bee space can be equally divided
between top and bottom.

To answer the first question we have to look at the bee space and how the
bees use it. This is widely reported as being between 6 mm and 9 mm. but it
is not a "variable" quantity, it is either 5.5 mm + or - 0.5 mm or it is 9.0
mm + 0.0 mm - 1.0 mm.

In other words there are two distinct bands of possible bee space and these
occur because in some situations the bees will work individually but in
other situations they need to be able to work back to back.

Much equipment is designed for a space of 10 mm when new, in the knowledge
that the box will shrink in use and the bee space will still be within the
range of 6 mm - 9 mm. This 10 mm space is usually divided into a chunk that
is 9.0 mm and a chunk that is 1.0 mm.

To address the second question is a little more difficult because it relies
on human judgement and not the judgement of the bees. The bees will
"automatically" respect a space of 6 mm or 9 mm because it is "natural" but
the bees themselves are not bothered how this space is achieved.

This comes down to management and standardisation. I live in the UK where
our "British Standard" hive has bottom bee space, the majority of langstroth
equipment used in USA will be top bee space, and many langstroth boxes in
New Zealand will have half the space in the top and half in the bottom. I
personally prefer the top bee space but use equipment that in all other
respects is "British Standard". (I used to be a UK equipment manufacturer
and so could readily accomodate non standard items.)

The bee space applies between boxes of frames and between any adjacent
parts, except the bottom brood box. The space between the bottom of the
frames and the floor inner surface can be more or less anything over 9 mm.

The standard in UK is 22 mm although some use 19 mm, and that is with the
extra 9 mm space in the box under the frames giving 31 mm or 28 mm. I have
seen them as deep 63 mm but they mostly had slatted racks.

If you are troubled by brace comb between the bottom of the frames and the
floor board, then I suggest that your bees did not have enough room at the
right time. The odd knob or stool of brace comb would not be considered
unusual.

In some circumstances bees will build crescents of comb between frames and
floor, these are shaped rather like turbine blades and help the bees to
ventilate more efficiently.


Regards From:- Dave Cushman, G8MZY
Beekeeping and Bee Breeding, http://website.lineone.net/~dave.cushman
IBList Archives, http://website.lineone.net/~d.cushman