roof insulation upgrade (sorta off topic)

realolman

My wife and I are looking at possibly buying a log house. It obviously has issues with roof leaks.  I believe it is an ice dam issue due to lack of insulation.  Guy says they have the ice shield stuff on there now.



It appears to me that the roof consists of log rafters covered by tongue and groove boards with ( I assume ) a couple inches of foam board and then a roof deck and asphalt shingles.



would anyone have any suggestions / ideas about how to improve upon that?  I thought about possibly removing the shingles and framing out a roof 6-8" above the existing foam board and filling it with spray foam and putting a deck and shingles above that. That would cause a strangely thick facia though.



 Any insights or suggestions would be appreciated.