<<<<<What is the beeway that you talk about? Please give an explanation and
description. I am totally unfamiliar with the term in relation to a top
cover. >>>>>>
If only people would read a book.  Supers welded together with extra comb,
burr comb on the top bars and on the cover board,  all completely
unnecessary.  The answer was given to us one hundred and forty five  years
ago and it is clear from all the discussion lately that the message has not
got through to many beekeepers.  It was given to us by a beekeeper  whose 
name is perpetuated world-wide in the Langstroth hive.
Bees will respect a space of approximately one quarter to five sixteenths 
of an inch. Less than this they will build burr comb, greater and they will
insert cells.  Thus maintaining this gap between top bars and excluder,  
bottom and top bars of adjacent supers and finally the cover board will
result in easy operation and little or no burr comb.
In England hive bodies are made this much deeper than the depth of the
combs.  The beeway can be top or bottom but the usual practice now is to
have it at the top.  We then have a wire excluder flush underneath and with
a quarter inch lip above to give correct clearance to the first super.    
With bottom beeway the excluder would have to be reversed. and the cover
board would need a lip.
It is essential that the beekeeper settles for one system or the other.  
Mixing them up is disastrous as there will be no beeway or double with
bottom bars stuck firmly to top bars or extra comb  between.   
Beekeepers contemplating making hive bodies must realise that  accuracy of
depth is vital, a quarter to five sixteenths inches more than the depth of
the combs.              Sid P.