Consider Preservation and Energy-Efficiency
 
You value good materials.
Antique wood windows are constructed out of first growth timber. The wood is much denser and more weather resistant than today’s tree farmed softwoods. Delicate profiles are possible because of the density of the wood. The reason these windows are still around, even with years of neglect, is because the wood is of very high quality requiring no cladding or additional materials to give them weather resistance. Minus all the ugly paint, your wood windows are usually quite beautiful, graceful, and strong.

The greenest building is one that is already built.
Replacement windows are touted as a way to save energy. But when evaluated from the perspective of the entire production, shipping, installation and removal process replacing windows consumes a whole lot of energy. Viewed another way, an older building has a great deal of embodied energy. If the total energy expenditure to manufacture replacement windows is considered, the break even period stretches to as much as 60 years. In the words of Richard Moe, President of the National Trust for Historic Preservation:

“We can’t build our way out of the global warming crisis. We have to conserve our way out. That means we have to make better, wiser use of what we have already built.”

Repairs and restoration work are done by local craftspeople paying local taxes. They use a minimum of materials and resources and a maximum of labor. Restoring windows is the best use of your existing materials and the best way to support the local economy.
 
You really can save on heating costs.
According to the Field Study of Energy Impacts of Window Rehab Choices* conducted by the Vermont Energy Investment Corporation, the estimate of first year energy savings between a restored wooden window with a good storm window vs. a replacement window was $0.60. Yup, less than a buck. In their conclusions section they noted “The decision to renovate or replace a window should not be based solely on energy considerations, as the difference in estimate first year savings between the upgrade options are small.” Broken glass, failed glazing, no weather stripping – these small and repairable items are what really effect energy efficiency in windows.

You want to avoid vinyl.
Poly vinyl chloride (PVC) is becoming one of the greatest concerns in the building industry. Not only does the production of it create an environmental nightmare, but the gases it emits over time are becoming a concern. Heaven forbid your house catches fire, and PVC burned will release toxic amounts of dioxin. If you are concerned about our planet’s health you should read up on efforts to reduce the use of vinyl.

* University of Vermont School of Civil and Environmental Engineering and the U.S. Army Cold Regions Research and Engineering Laboratory.