I’m still working to become a home inspector, how be it rather slowing
because of work. I’m currently working in construction. The house that I was
just working in has been insulated in a manner I haven’t seen. It has closed
cell foam insulation that seems to be about an inch thick, maybe a little
more but not much. I can’t see the walls, but in the attic it is sprayed on
the underside of the roof. They do not have singles, but some slate looking
stuff that appears to be some form of plastic. My concern is that they have
tried to enclose the whole house, including the attic, into the living
space. There is not insulation between the ceiling and the attic. The home
owner said this is what they were told would be best. Just seems like
heating the attic would be a waste and that the inch or so of closed cell is
not enough.
What you described seems like the common practice I have seen (which is not very much in my area) with closed foam. I have been told that one inch of closed foam is about an R-20 rating.
Maybe somebody how has dealt with this more will come along and answer.