Have an energy audit done. It will identify where your losses are and how much heat/cool you are losing. It should also provide recommendations on how to improve the situation. Armed with that information, you can do a cost comparison.

Energy audits are often offered at no cost or subsidized rates by your local power provider.

above posts are correct.

most energy loss is through the roof/attic.
adding insulation in an attic that has air leakage to the conditioned space below won't save you money.
first you have to stop the air leakage sites.
this is the air barrier between these two areas.
once the air barrier is complete..then add insulation.
if your heating system and/or ductwork is in the attic
address issues with them before insulating.
once insulation is added it is difficult to work in attic
so address all other issues first!
visit www.natresnet.org
for a list energy raters in your area.
best of luck.

THanks all! Very helpful suggestions, especially re: windows. I was suspecting as much and it's good to hear that I can do some other things first. My neighbor, with a similar aged house, had an audit done last year. I'll have to probe them about the results and look into one myself. I'm also very interested in figuring out about our furnace re: Jake2007's suggestion. Here's something that I have just no idea about. We have a Trane XR90. What does that mean? And I'm also very interested in measuring our attic insulation.

Thanks again.

I agree lower cost savings should be done first. Such as sealing and insulating. Then take a hard look at those old windows.

We added vinyl double pane low E windows 3 months after we bought our house. Replaced aluminum double panes.

We offered on house in late September when it's still warm here in AR. We had problems with cold drafts soon after we moved in early December. We had a hard snow storm 2 weeks later as temps dropped down into the low teens. I woke up the next morning and there was at least an inch of ice build up on the inside of our bedroom windows! Starting looking at all the windows and realized condensation had been an on going problem evidenced by warped window sills. I should have caught that before we offered, although I did notice fogged window panes indicating problems with some of the windows for which we asked and received a $1,500 repair allowance at closing. Still, I was not happy that I missed the deplorable condition of the windows. Life is full of lesson I suppose!

Immediately began the process of shopping for good windows and a good installer. 8 weeks later, we had $7,500 worth of new windows. Keep in mind we have 1" foil sheathing all around the exterior of house, walls are insulated as well as possible without going to extremes to improve and attic had 6" of blown cellulose.

After install, no more drafts!! Gas bill for those first 3 months of winter (and those 3 months are winter in AR) averaged $255 and 187 CCF of nat gas per month.

Highest average in the 4 winters since has been $191 and 136 CCF of nat gas.

Overall nat gas savings has been right at $300 per year.

As for electricity, I didn't have to run A/C for those first 3 winter months, but a heat gain calc on my house shows the windows gain 3 times the heat over what the loss is, so I would think the electricity savings would be 3 times greater in kWh than for CCFs. I would estimate that, based on known kWh cost usage, at $392 a year.

So the windows cut my utility costs by $692 a year, or 29%.

I'm pretty sure I wouldn't spend $7500 on new windows to save $300 per year on gas, but getting rid of leaks is a good thing year-round.

I believe radiation is a big second but it's double-edged. During a/c season you don't want any; during the winter it's a good thing. I'd think a transmission-controlling 'storm window' would be the best solution.

And note that low-emissivity glass is about 90% hype. It helps, but good absorption films are about twice as effective, iirc. (But maybe narrow-band films that don't darken the glass in the visible are very expensive.)

And for anyone with leaking double-pane windows and basic handyman skills, replacing the Insulated Glass Unit is really just a matter of figuring out how it's held in the frame. For plain glass here in Los Angeles, I was quoted $80 for a unit about 28" x 38" (plain glass). Note that the first shop wanted about $280. Afaik glass shops don't fabricate these themselves, but send out for them.

johnax,

read my post again!

I estimate my savings for the new windows at $692 per year, not just $300. That is an annual return, tax-free, of 9.25%.

Pay attention! You might just learn something!

I did research and found the best return on investment was to replace my exit doors and use storm windows. Plus I got to keep my original windows that match the house woodwork. I'm going to add more attic insulation. I had to replace basement windows for looks so I got low E glass windows.

cheeck out your walls! that age home probably has no insulation in the walls at all. call usa insulation or find injection foam in your area

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