a vegetable garden on an office roof?

[Alex Hunt]

Hi,
a friend has the idea to grow vegetables on the roof of the office building that his catering company works in.

They have a large area of south facing flat roof, that has an asphalt covering. I understand that due to the thermal properties of asphalt, if we put any point loads on the roof it may be detrimental to the roof covering. Is there a way to spread the load effectively so that we could put ten separate pots growing herbs and salad on the roof area without negatively affecting the roof covering itself?

Any ideas and suggestions gratefully received.

[Julia Bennett]

Bright Green (!)

I'm guessing you are thinking that the roof surface in summer is more plastic at the higher temperatures and therefore more vulnerable to the pots damaging its integrity.

Some kind of enclosed sand bed perhaps?
Or a framed turf bed with sedum tucked in for longevity ? (see DIY Green Roof thread)
Anything 'soft' that spreads the load of the pots and stabilises the temperature of the roof beneath.....

What about pots all around a large shallow pool for rainwater collection (for watering) and summer cooling...? You'll never get the staff to go indoors!
Just a thought.
Joolz

[Alex Hunt]

thanks Joolz,
sorry for not responding before, I thought the system was supposed to tell me when someone replies? all ideas we came up with too, we even looked at a cantilevered system from the wall, but in the end the idea was squashed by the owner of the building who wanted nothing to affect their potential sale to a new owner...

something for next year perhaps.

Alex

[Nick Grant]

Alex

click 'notify' to be notified, does work.

Nick