2nd dilemma: Insulation (i.e. more insulation)

Given that the house was built in the 50s, I had assumed that there was a certain amount of insulation in the walls and roof.  However, I knew that it would need to be upgraded to today's standards.  So, the plans had always been to install new code-compliant insulation in the kitchen and upstairs bathroom once they were gutted.  We also planned to wrap insulation around the ducts in the garage as there is no sense losing heat and a/c in the unheated garage, to furr out the basement walls and add rigid insulation between the furring, and to install acoustic insulation in the new basement bathroom walls.

Joe, as usual, did a great job.

 

The plans had also been to leave the walls and ceilings outside of these spaces alone since the plaster was in good condition and we figured they had some insulation...  However, knowing that there was only 3-1/2" of insulation in the roof was nagging at me...  Then, a neighbor told me a story that started keeping me up at night:  the previous residents had complained that the furnace didn't work because they were always so cold.  Well, Mark, our hvac guy from L & F Heating, had told me that the existing furnace was only 6 years old (even encouraged me to sell it on Craig's List), and that the only reason for replacing it was to get a higher efficiency (95% instead of 80 some)...

So, how do I justify the expense of taking perfectly good ceilings down and then putting them back up?  Plus, I couldn't just use regular batt insulation since the roof cannot be vented...  I'd have to use the more expensive foam insulation...  But, now was the time to do it  - it'd be an impossible task for a homeowner once they've moved in...   After talking to several insulation companies in the area and more sleepless nights, I decided to take the ceilings down and fill the rafter spaces with open cell foam.  And, while we were at it, they might as well foam the kitchen and bathroom walls.  What the heck!  I was already spending money I hadn't budgeted for, so what's a few hundred more!!!