"Dan" wrote:

However I plan to have ALL the fiberglass
removed & replaced with new insulation. I am wondering if there is any type
of insulation, maybe a rigid foam board material, or something sprayed on,
which is resistant if not impervious to rodents getting into it, on top of
it, pulling it down & nesting in it. Any helpful insights into this
appreciated.


Don't know how rat resistant it is, but you might consider something like this:

http://www.tigerfoam.com/

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