I'd want to know how the panels of polycarbonate are sealed so insects
and water don't get down into the channels.
Great idea would be to have a propagating end to a greenhouse that has
polycarbonate whilst the rest has safety glass!
--
Janet Tweedy
Dalmatian Telegraphhttp://www.lancedal.demon.co.uk

You can get end caps for the sheets, but you can just tape them with a
GOOD tape.
Why would you want safety glass?
Whilst polycarb does let in slightly less light than New, Clean glass
this is normally compensated for in commercial houses by needing less
glazing bars, and less steel in the framework as it doesn't have the
weight to support.

David Hill
Abacus Nurseries