Our 1994-95 constructed (and current house) is R30 attic, R19 overhangs, R13 exterior walls, R11 unfinished lower (basement) level. Windows are double pane thermal insulated.  Looks like we could update our attic but exterior wall changes could be expensive due to lack of depth and requirement to remove siding or interior wall board.

All still a lot better than what I expected to be standard in other parts of the world.

I can swear there ain't no heaven but I pray there ain't no hell. _ Blood Sweat & Tears