Greetings! (My first pinhead inquiry)
My home village, a suburb of New York City, has ruled out consolidation
(sorry Mr. Stahl) of the wood windows on its not-so-historic 1920's brick
Municipal Building.  They still want to preserve the appearance of its
average 3'-4"W x 9'-4"H D.H. windows, each sash 9 over 9, (up to twice that
width with fan head) windows.  Thermal rating (insulated glazing),
operability and performance are still a concern, as well as (you guessed
it) cost.  There is a serious consideration for aluminum clad wood, all
wood is a lot pricier, all aluminum is a lot fatter, and then there's a
local low bidder who is pushing solid vinyl (?!) that will not stack up in
appearance.
Is there any good analysis, otherwise concensus, or, I'll settle for
informed suspicion as to how these various systems perform in such sizes?
While we're at it, how about vinyl clad wood or the paintable fiberglass?
--Jim Rhodes