We have a second lake home with an exposed 2X8 dougfir rafter ceiling. Shealthing is 1X10 pine boards with shingles directly on top of that. The building was built in 1956 and intended as a summer cottage but we want to use it year-around. I want to insulate the roof. I'm thinking of removing the shingles and applying 2" foam board, re-shealth with 1/2 OSB and shingle over that. I've also thought about installing an additional 1" on the inside between the rafters and covering that with beadboard and paint to brighten the ceiling while allowing the rafters to show through. Anyone else have better idea?