I recently bought a 60 year old cottage that's originally a log cabin plus 2 additions over the years. The attic spaces do not connect and they are insulated but unvented. The asphalt shingle roof is 20 years old and still in decent shape--I have maybe 5 years before needing to replace. My question is about the insulation. There is R13 foil-faced fiberglass on the ceiling and stapled up in the rafters. Is this OK or would it perform better if I pulled down the rafter batts & laid them on top of the ceiling batts?