I have a home built in 1970. It has a flat roof. In the1980s, a pitched roof was added to the top of the existing flat roof. Now when you walk in the attic, you walk on top of the roof. I would like to add insulation in the attic, on top of the old roof. I noticed during a remodel that the cieling insulation has shrunk or never filled the void in between the roof beams. Here is a rough section image of the situation:
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I have no doubt that adding the insulation will have some benefit, but I'm not sure how efficient it will be with the air gaps and extra structure (old roof) in between.Ideally, would all of the elements drywall/insulation/old roof/new insulation be set if they were flush together, without the air gaps?
Thanks for any thoughts on the matter,
-J