[Greenbuilding] Stone Slingers to place soil for Living or Green roofs.

[Chris Green]

I had a revelation at work today while discussing things with a 
co-worker. We have been hiring an operator with a "precision aggregrate 
placement machine" called a Super Stone Slinger to place sand and gravel 
for under the flooring slab, and to place crush for drain rock.
On another site with another company, the same operator placed a 1' lift 
of top soil over the whole back yard (from over 50' away, since he 
couldn't drive over top the natural gas pipeline placed there...) in 
maybe an hour.

A Stone Slinger is basically a dump truck with a variable speed conveyor 
belt underneath it which can be aimed. It's vaguely like having a fire 
hose to blow anything from gravel to fine topsoil to wherever you want it.

To see what one of these machines look like, this company makes them:

http://www.superstoneslinger.com/

So, my revelation was that this machine in the hands of an adequately 
experienced operator could carefully place the topsoil you need on most 
residential roofs built to carry the load of a living roof.
Very quickly.
Place, say, 9 cubic yards/18 tons in 20 to 40 minutes.

No need to hump the soil up there in buckets or jury-rig some kind of 
hoist..... and the service would probably cost a lot less than manual 
labour, if you're paying for that.
For the really brave, you can stand in front of the stream of material 
and direct where it lands with a sheet of plywood (that's how we kept 
the crush out of the footing forms on Friday...Rob and his helper didn't 
seem to be too badly sandblasted afterwards... :-) )

As a safety matter, you would want the soil distributed fairly evenly as 
the placement goes, rather than pile lots in one place and none in 
another. I once saw an arched roof/ quonset hut type building (a curling 
rink) where the snow softened up on the sunny side of the roof and slid 
off, leaving a deep layer of densely packed snow on the cooler shaded side.
The building then collapsed due to uneven loads.
Fortunately, no-one was inside at the time.

Just thought I mention this if idea if anyone can use it.

Cheers,

Chris Green.