The walls of the house originally had insulation consisting of two sheets of aluminum foil that were seamed all around to leave an air space between them. When R-50 became fashionable, back in the 80s, white fiberglass fluff was blown into the walls with care taken to flatten the aluminum insulation against the inner wall as a vapor barrier. It is remarkably effective.
The main floor addition is insulated with pink foam panels that were cut and carved with a Sure Form file to fit snugly into every gap and crevasse. The flat roof above its ceiling has eight inches of pink fiberglass, as does the part of the floor that is open beneath. In the rest of the house, the bedroom level—fourth of the five levels—has eight inches of poured cellulose (fire retarded) over 10-mill plastic sheeting that encases the ceiling joists, and on top of that is a thick layer of pink fiberglass. The top floor roof is filled with fiberglass and the knee-walls there are backed with fiberglass. You won't find a better insulated house anywhere.