I think you left out an important bit of information in the HP123 article on “Home Heating Basics”—the cost of a heating system. I know that costs vary depending on the capacity, type, and extent of the system, but I think most contractor-installed systems on reasonably sized houses are in the $10,000 to $15,000 range.
I would like to suggest that if you insulate walls to R-30 and attics to R-50, build the enclosure relatively airtight, and incorporate even just a bit of passive solar design, you may not need a “system” to heat it, even in cold climates. A small gas or propane-fired, modulating, direct-vent space heater will do fine.
The efficiency of a particular unit that I’ve installed is 81% to 84%, and the installed cost might be about $1,500. Low efficiency, you say? Yes, but with a $65 per month gas bill for space and water heating in a 7,200 heating-degree-day climate, I don’t think efficiency should be the issue you make of it. To quote Alex Wilson, “It doesn’t make sense to put in a $10,000 heating system to provide $100 worth of heat a year.”
Steve McCarthy, Starbright Energy Services • Wellsboro, Pennsylvania