value vs. cost of replacement double hung thermal windows?

Maybe not on heat savings, but it would give you windows that open/close. I’d do it just for that reason.

-- Our village hasn't lost it's idiot, he was elected to congress.

I dont know how to figure “the math” on such an upgrade, but I’d have to think that double pane, double hung windows in place of single pane windows would HAVE to be way more energy efficient.
And the added benefit of being able to open them when it’s nice outside would be nice too.

-- Perform A Random Act Of Kindness Today ... Pay It Forward

http://www.energystar.gov/ia/partners/manuf_res/windows/ES_Windows_Cost_Energy_Savings.pdf

Now the downside is there are several papers that have followed government assistance programs geared towards installing energy star windows that have shown actual savings is grossly under the calculated values.

I would also replace them just because I would want to open and close them and I am sure there would be some savings observed.

As mentioned before, it is near impossible to do the math on something like this, as you would have to know how much heat/cool loss you are getting from the current windows, what the cost/value of that loss is, and then you would need to know what the improvement in efficiency would actually do to that loss of heat/cold. Then determine the cost/value of that change. We just installed new windows in our entire house. It was a decision less based on return on investment for energy savings and more based on the fact that we will see some energy savings but the aesthetic (and in your case the ability to open/close) as well as some increase in resale value of the house were the drivers. I don’t think the cost of windows really pays for itself in a reasonable amount of time. So it should probably be a decision based on what you want, rather than whether it makes sound financial sense.

-- Matt - Phoenix, AZ

I don’t know if this a consideration at all for you, but we were shocked how much noise new windows block. Just amazing and it made the expense easier to take.

$110 is a 1/4 what I paid for my windows. No tax credit the year I had them replaced.

-- I always knew gun nuts where afraid of something, just never thought popcorn was on the list.

The new windows will make the space much more comfortable as well as the benefits mentioned above. The room will stay more evenly heated/ cooled and you will not miss the drafts you probably have now.

Thanks everyone for the ideas and advice.

I have a lot to consider before I make the decision later today.

-- "I love it when a plan comes together" John "Hannibal" Smith

I have a 111 yr old Victorian. 19 double hung, wood windows, all a mess. I struggled with this decision also because I really wanted it to remain original as possible. However. Windows are for the inside of the house, not the outside. I replaced them all with similar to what you are looking at, from Window World. Best decision I could have made.

-- Sam Hamory - The project is never finished until its "Finished"!

Get the internal grids if it is an option. To me it looks wrong on older homes not to have them.

-- I always knew gun nuts where afraid of something, just never thought popcorn was on the list.

The return on investment is lengthy based solely on the R-factor of the different windows, but the difference from infiltration from leaky old windows is pretty big. We had old single glass sliders in aluminum frames that rattled and leaked a lot of air (built in 1968). Also, you will notice a pretty good reduction in noise from outside. We live about 100 yards from a train track, and the only place I hear the train is in the bathrooms, from the vent fan flue. If noise is an issue, you can go with a 1/4” pane on the exterior. I did not use that, just two 1/8” panes, with the grids.

-- Steven.......Random Orbital Nailer

Also, check with your electric company. Sometimes if you upgrade your windows, they’ll give you some kind of rebate on your power bill.

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