'Mike' wrote:
"Jo" wrote in message
...
I would like to erect a greenhouse at some point in the future and wondered
what experiences people have had with the different types ie glass vs
polycarbonate.
Any advice/tips would be gratefully received.

If you live in a windy area, forget polycarb, unless you want to keep
fetching the panels back from your neighbours and replacing those which have
broken :-((

Twinwall polycarbonate when properly locked into a frame is a heck of a
lot more resistant to damage than glass. I keep a sheet with a plank and
a pair of bolts through it for emergency storm repairs. Glass shatters
when hit by flying branches and chunks of roof - it bounches off
polycarbonate.

If you intend to heat the greenhouse then twinwall polycarbonate glazing
is the way to go. The frame needs to be made more rigid when plastic is
used - the corner diagonals on the prevailing wind side must be made
stronger at the very least. And you have to make sure the stuff cannot
spring out even if the flexure from wind loading is significant.

I have never had a polycarbonate panel break. I have had one go into
orbit in a major 100mph storm and it flew a couple of fields away before
it trapped in a hedge. Chunks of corrugated iron off a neighbouring farm
were flying around that night. Glass just shattered totally on impact.

Regards,
Martin Brown