29-year old house near Portland, Oregon. Looking under my house, I see insulation attached (stapled) to perimeter of my foundation. It is just hanging lose--not attached at the lose end to either foundation or underside of floor (the tongue and groove boards). If I attach it to the underside of floor, the shiny side will be up against the floor.
Question 1. Did my builder do this correctly?
Question 2. If what I have is not useful/correct, What should I do to remedy this?
Question 3. Should I be insulating the underside of the floor?
Question 4. Should I be insulation the bare foundation walls?