[Greenbuilding] Tip of the day - recycled insulation

[Alan Abrams]

<Last year we had a relatively small section of flat roof  re-roofed.
It turned out the old roof was insulated with 1 1/2" extruded polystyrene. 
It further turned out that it was done in a manner way that a good chunk of 
it was salvagable.>

good comment.  although it is thermally and vaporously outstanding, I still
have misgivings about the floors, walls, and roofs we have blasted full of
sprayed-in-place PU foam; in the coming days with no more trees, future
remodelers, recyclers, and deconstructors will rightly curse me, flipping me
the bird with a finger blistered, bruised, and torn from scraping away the
foam.

we do keep this fuming remodeler in mind, and design where possible flat
roofs (designed for vegetated roof loads), with rigid insulation laid on top
of the roof membrane (and under a root barrier membrane).  This way, someone
can deconstruct or add another story and easily reuse the insulation.

-AA