When I bought a roll of R-19 fiberglass insulation the other day, the guy in the orange vest had to cut open a package of 6 rolls. As he cut the plastic outer wrapping the 6 rolls expanded by a considerable amount...let's call it 50%, but the numbers don't really matter.
Then when I got home and cut open my individual roll, it expanded once again...let's say another 50%, but again the numbers don't matter.
That tells me that the manufacturer is quite happy to compress the insulation by a considerable amount for an extended period of time.
So here's my question:
If I put the 1/3 roll that I have left in one of those vacuum storage bags and compress it down as far as I can, will it bounce back to it's full size (and R value) next month, next year, next decade?
In other words, how long can insulation remain compressed before it looses it ability to perform at it's original specs?
P.S. those bags will indeed compress the insulation down by a whole bunch! BTDT, last night.