"Christopher Norton" wrote
JennyC" contains these words:
"Christopher Norton" wrote
The design requirement for a man load on flat roof joists will
mean
it can carry almost as many growbags as you require.
Loading is almost certainly not a factor in this case. If you
want
me to check then get the size of the flat roof joist, with the
longest
distance between supports and I`ll do a quick calc to prove the
loading for you. 8-)

What if there are no joists ?
My flat roof is made by flat concrete panels.........
Jenny

Then I`m of no use whatsoever. I`m a timber engineer. Chances are
tho
that the design requirements are the same. BS codes have that effect
now. If it`s old then I`d be very carefull.

I was !! I had wild plans for a shallow pond with a waterfall type
affair on my roof garden, but luckily found the architect who build
our house and he told me that the roof could carry 150Kg per square
meter. My water feature would have been double that............. So
now I have heavy pots situated over the weightbearing walls below and
around the edges...........:~)

Jenny
Greenhouse in the sky pictures at :
http://members.rott.chello.nl/ldejag...ex.welcome.htm