I purchased a home built in the 50's. The exterior is brick. I removed some interior paneling expecting to find a wood frame celtex and empty wall cavities. I found concrete block. Now I longer worry about tornadoes but I need to insulate my home. I am planning a complete gut including the ceiling and the 4 inches of cellulose in the Attic.
For the Attic I am planning on two layers of fiberglass R19 and R38.
For the walls I was planning on attaching foil bubble wrap to the existing furring strips for a radiant and moisture barrier. Then stud out the inside and R13 insulation then dry wall.