I am not sure that Fiberglass is "greener" or more efficient and that also depends on what you are comparing it to. Fiberglass with have better thermal numbers than even a thermally broken aluminum. I would not eliminate a Aluminum clad wood (I think that is what you Weathershield option is) window from your selection options if you decide you want to another option. All things considered, you are going to have a hard time matching the aesthetics or build quality of that Marvin Integrity. Biggest issue with that window is the stock size program. That is a moot point in a new construction application because you can build it to whatever you need it to fit. That would be my choice if I were building right now.

I guess I agree with Ron; it's not that hard to get estimates. It takes a few seconds to write down the three sizes you need, and the window company of your choice can give you a quote on wood vs. clad windows. Generally speaking all-wood windows are maybe $20-$40 less than wood clad windows. When you add the price of paint and possibly add the price of labor (your own labor is free, sort of), you're not really ahead. Also, you'll have to repaint the windows every 5-10 years or so, unless you hire someone before then to wrap aluminum trim around them.

East Bay 10 - thank you for the details....very good info. HomeSealed - yes, the issue with peeling paint is the interior surfaces. I do think that condensation contributed to the problem. On some very very cold days we'd even have ice in the interior bottom corners. (Looking forward to winters in the South!) When the paint pops off, it leaves bare wood. I would think if the wood had been properly primed, I would at least see some paint left in the grain. But the wood is completely bare. In the South we will face more intense UV exposure so there is damage from that. Perhaps we will look into fiberglass windows. Is Marvin the best player in the fiberglass market?

More suggesting it because there are options to have a wood interior with a non-wood exterior. Wood is great and a lovely material, but there are better options in many cases if you are not compelled to use wood via some sort of historical guideline.