My wife and I are building a new home in Abilene, Texas. I am using structural insulated panels on the walls and roof. Having spent premium dollars to get top R-value on the enclosing envelope I find the degradation of that envelope by low R-value windows and doors lamentable. My research indicates that in addition to the obvious (spectrally selective, low-e, double pane) I would be wise to specify foam filled vinyl or fiberglass frames on the windows.

My dilemma is that I can’t seem to find a window manufacturer/installer that offers foam filled frames in my region. Consequently I am unable to weigh cost against performance (i.e. return on investment). I would consider ordering the windows from a manufacturer in another region but a lot of them seem to tie their warranties into the installation. Does anyone have a recommendation?