Hi Elizabeth et al:
 
When experienced beekeepers recommend using only 9 frames in the brood
nest, they are usu. talking about older, used frames.  With new frames and
foundation, always use the full complement of 10 frames, so all combs are
built nice and even, and to uniforn thickness.  And make sure the frames
are pressed tight together, shoulder-to-shoulder when you are closing up
the hive.  (The extra space should be about equal at both side-walls.)
 
After a few seasons, there will be some buildup of wax and propolis on the
frames, and sometimes they swell a bit due to moisture.  For that reason,
many beekeepers DO use only 9 frames in the hives.  I for one certainly
prefer this. The combs are almost (not quite) as close together as with 10
frames, and the balance of the extra space remains at the side-walls.  This
arrangement improves ventilation and makes hive inspection a bit faster
(which is more important if you are operating larger numbers of hives).
Some would argue against this, but it is more of a personal preference.
 
Brood comb spacing in nature is usually around 1 3/8 " center-to-center,
but it can vary to more like 1 1/2", and some hives in Europe are actually
designed to maintain the wider spacing (frames are 1.5" wide).
 
I must disagree with Lloyd about 9 vs. 10 frames for brood, though.  He
mentioned that the queen won't use the end combs, so you only end up with 7
containing brood.  I find that this is not necessarily so.
 
I have often seen brood right out to the walls, and even so, since
virtually all brood chambers are comprised of two boxes, not just one,
there is never any lack of space for the queen's laying anyway.  She
certainly doesn't need all of 18 or 20 combs, so this whole issue really
isn't of any significance in that regard.
 
Well, anyway, I hope you find this information helpful.
 
Regards,
Joel Govostes
Freeville, NY