This may be too technical for alt.home.repair so I'm posting here:
Natural Resources Canada uses the following program to calculate rebates for energy efficient home upgrades.
Download from:
formatting link
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 4.5It 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?