I've recommended that a roof be cleaned. Its a stone ballast membrane
roof, but the ballast has acquired massive amounts of organic
material, mud, dirt, etc.  Any idea HOW such work is actually done,
or what kind of a trade or contractor would do it?

If it were my house, I suppose I'd get up there with a plastic snow
shovel and screen all the stone, and then hose the debris into the
gutters.  But, this is not my house.  This is one of them modern
buildings with the roof drains that go down into the building,
collecting under the main slab.  If something clogs up in there (and
it may have already done that on one occasion) its going to be an
awful mess.

So I suppose one shovels the debris over the side where it can be
collected, moved by wheel barrow to someplace where it can dry and
then disposed of.  Does that sound reasonable?

-jc

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