"Paul D.Smith" wrote:

Can't recommend a company but I can give you a newbie heads-up. I was given
a second-hand green house. I laid a concrete plinth and built it upon this
secure in the knowledge that the greenhouse was very heavy and would be
there for years to come.

WRONG! The wind blew it about 6 inches across the garden. Fortunately the
mastic & glass meant is was rigid enough to just slide without breaking any
panes but getting it slid back was "fun".

You were lucky. Wind loading can annihilate a greenhouse if it jolts it or
breaks any panes facing into a gale force wind. Once the wind gets inside the
strongest gusts can spring out glass from the clips.

Now it's bolted to the concrete!

You should also reinforce the corner that faces into the prevailing wind. The
stock material on most amateur greenhouses is usually too weak and inclined to
bend or buckle during 80+ mph storms.

BTW, glass is much stronger than you might expect. I have a 14 month and a
3 year old and apart from the impending attack of footballs and the like
(odds are my "return kick" will be the first one to break a pane!), I don't
worry about the glass.

You should! As a youngster I ran through a greenhouse window and luckily got
away with it. Chicken wire mesh on wooden batton standoffs will prevent any
nasty accidents with small children. The worst risk is putting an arm through
the glass and severing a blood vessel. Horticultural glass can form very sharp
daggers.

For a heated greenhouse you should seriously consider twinwall polycarbonate.

Regards,
Martin Brown