I'm currently about to embark on the insulation stage of my 1700 sq/ft one floor house. The main room of the house consists of the great room, kitchen and dining room which are all enclosed under a vaulted ceiling which starts at 9 ft and vaults to 14 ft. The rest of the house is flat 9ft ceilings. We are doing radiant in floor heating with a modulating condensing propane fired boiler and a pellet stove in the vaulted area.

My issue is insulation. I have already budgeted for and am going with 3 inches of closed cell foam in all exterior walls.

My question is the ceiling. I want to insulate part of the ceiling with close cell spray foam but don't want to seal up my soffits or ridge vents. What I have been told I can do is spray 1.5 inch of closed cell foam down on to the drywall of the ceilings (which would be a vapor barrier) and then insulate the rest with cellulose, blown in fiberglass or fiberglass batts. 1.5 inches of CC foam is about a R-10.5 and I would need a total of R-49 in my attic. The attic space is not usable and will be sealed up completely when done.

Different companies have told me to go with different insulations and I don't know which one to choose.

Right now I am leaning towards doing the 1.5" CC in the vault and then batting the rest of it. My concern with blown in fiberglass or cellulose is that it would settle over time with the vaulted ceiling.

As far as the attic flats, I do not know which type of insulation to go with over the 1.5" of closed cell. I have had estimates and reasonings for using either cellulose or blown in fiberglass to get the remaining R-Value that I need. I'm not sure what to go with.

I was also concerned with my house being "too tight" with all the CC foam so I did consider either doing the flats with no CC at all or just a thin layer that would not be as much of a vapor barrier as 1.5" then insulating over that. The reasoning would be that I would still get the air barrier but would be able to allow some moisture to escape to the ridge vents.

I do not want to have to install a heat/air exchanger. I live in Upstate NY so our winters can be freezing and summers can get hot.

I'm not a contractor by trade and this is my first dabble with home construction so I am kind of learning as I go.

Any input/advice or suggestions would be greatly appreciated.

Sorry about the spelling errors. I'm part of the "spellcheck" generation.