What is the best way to insulate a one-and-a-half story home? Our house was built in 1952 and has no soffit vents but does have attic vents. I did some research and am leaning toward using Icynene closed-cell foam to create a “hot roof” – but what I've read is to do it right we'll need to either remove the sloped ceilings or remove the roof. Is there a way to insulate our home properly without removing either the roof or ceiling?
I'm guessing you have what's called a cathedral ceiling - that is, roof rafters, insulation in those rafters, drywall under it and plywood above it. Like a rafter sandwich.
For starters, Icynene is an excellent choice. I've used it myself, with fantastic, money-saving results. In terms of installation, if this is indeed a cathedral ceiling, then yes - the roof or drywall have to be removed so you can pull out the old insulation, apply the Icynene, and close it back up. I essentially did both in my upper attic roof, in places where I could get under it. In the attic overtop my home's addition, I had little clearance, so I had to take the roof off and spray the Icynene across the ceiling. Even though it was a lot of work, it was worth it. Icynene seals and insulates, and is a very cost-effective way to keep your home heated.