This may be too technical for alt.home.repair so I'm posting he

Natural Resources Canada uses the following program to calculate rebates for
energy efficient home upgrades.

Download from:
http://www.buildingsgroup.nrcan.gc.c.../hot2xp_e.html

According to the technical report from this software, a one-story house with
a full basement 43' x 43' exterior dimensions with a floor area of 1600sqft
on the main + another 1600sqft in the bsmt results in the following heat
loss values at 19F on the north west coast.

Base values:
==========
Orientation: west
Window distribution: even, 15%, metal, single
Cathedral roof: R12 attic
Main floor walls: R12 on 2x4 wood
Basement walls: no insulation, mostly below grade
ACH @50kpa: 10.35 (ACH = air changes/hour)

Heat loss = 57k (seems low to me as most HVAC contractor recommend 80k or
more)

Upgrades: (cummulative):

HL
49k; Low-e, double pane, vinyl windows
37k; Add R20 to bsmt walls
32k; Upgrade attic to R40
28k; Reduce ACH to 4.5


It gets even better, annual fuel consumption is reduced from 215 million btu
to a mere 81, almost 2/3's. Can anyone here verify these calculations with
empirical evidence?