Here we are 0.12kwh double your 0.6 and considering resale value, and
the fact that gas was at its highest last year and electric will be
going up with gas you can halve your payback estimates conservatively .
Standards today are like comparing standards of 40 yrs ago to today.
Bottom line, a good return, increased comfort, and a value that wont be
exceeded in 30 yrs

Plus Labor is the biggest factor in increasing later , my cost to
double up was i almost just material. Plus doing it later would make
working in the attic impossible and dangerous, my ceiling is the attic
floor.

Now factor in settling of insulation , I will measure mine soon but I
can visibly see its settled.

6 inch ? a joke , thats apx 21 , in the 30s that was ok, but not now.

Yes diminished returns are a fact, But I paid no more than 66 $ to
heat 1275 sq last year, the installer knew of similar houses wasting
700 a month , I did allot more than the attic , I did walls windows
foundation, floor. But my resale went up 30000.

Utility co has been out and say my costs are among the lowest if not
the lowest. Yes they worked on my meter and checked for taps.

Figure it this way pay now or pay allot more later. Nobody knows where
gas is going, leave it to alcaida and it will be 100 a barrel with NG
and electric following right along.

Trends for utilities show a doubling in 6-10 yrs and antiquitated
standards insure we will be a worlds leader in waste, as always.