Well the plumbing run through the floors will leak at some point if it was done in the 50's if it's not already leaking.
Everyone of the Frank Loyd Wight homes have had to replace it years ago.
I'm very suprized that plumbing has not burst from freezing by now that far north, must be running anti freeze in the lines. Any form of plumbing is never ran through an attic or outside wall any more in your area by code.
How much insulation you need depends on where you live.
R50 is the norm. in you area R-50 is 12" of fiberglass insulation.
Last edited by joecaption; 11-27-2011 at 08:14 PM.