Andrew,
      Your post asked for more information on hive products made from
materials other than wood.  My only experience is with Wooden Hive
materials, but on the Web I ran across Per-Olof Gustafssons' (Of Sweden),
interesting web page:
 
http://www.algonet.se/~beeman/
 
If you go to this web site, then click on the 'How it all started' button.
  Within the text of the page,
you will see a link to Styrofoam.  Apparently they are High Density
Styrofoam, and from the
pictures on his web site, it looks like he uses a lot of them.  (But I dont
 think they are rodent
proof - Check out the picture of the badger Damage to a hive)
 
The Manufacturer is
 
LP:s Biodling
Torstensbyn 14
S-661 94 S


 
äffle
Sweden
 
His web page is pretty interesting.  I'd recommend surfing through his
      pages.
 
 
 
Hope this Helps
 
Rod Billett
 
Lexington, SC USA