Dufster, it is no secret what it takes to heat homes built to code. In my case it is $600 this season (for 5 cord of firewood). My utility bills are about $75/month which is the annual average including running the air conditioner. Last year we had a particularly hot summer and the air conditioning bill ran close to $150/month for nearly 4 months. But if I ran the natural gas furnace (cheapest "conventional" source of heat) it would be on the order of $1300 per season minimum and that would be with the thermostat set to 65. Those in rural areas are on propane and looking at more than $2500 per season. Perhaps you have been to hearth.com and read what people are going through the last couple of winters. .
You would have to be heating a corn crib to pay that much.
Did you notice Hugo Chavez donating heating oil to low income americans 2 years ago ? It seems to suggest that people cant afford to keep their homes warm. That seems to suggest that some will benefit from more insulation.
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Do low income people live in new homes with current building codes.
People who insulate beyond code requirement and apply passive solar techniques when the home is built will typically save over $1000/season in utility bills assuming they are on natural gas. That amount will increase if it includes a "cold roof" providing a benefit in summer. That doesn't sound like much now, but that is without taking inflation into account. And as we know, amortization on the insulation in your home runs over a very long period, typically several mortgage terms.
Nonsense, I built a new house for my inlaws 7 years ago. The "budget" payment for there gas bill just went done from $60/month and that includes gas hot water, gas stove and a gas clothes dryer. The latter of the three could easily account for half that gas.
Granted we have pretty strict codes already.