I am still looking for windows and another site raves about them as the absolute best...I haven't read anything here to reaffirm....Thoughts?

The Best for what? They seem like a good quality medium price window. They won't be as efficient or as expensive as a good triple pane. But I've heard many question whether the added cost of a triple pane has a reasonable payback period.

BTW, from an efficiency standpoint a double hung generally is inferior to a casement because the casement seals better when closed.

For comparing windows, go to the National Fenestration Rating Council, which rates windows independently for the various factors important when deciding which windows to specify.

Marvin windows have U- values in the 30 and 40 range, which is OK for double glazed windows. But good triple pane windows rate in the upper teens and 20s.

You may want to look at SERIOUS WINDOW. They run between R-4 to R-20. The frame material is an important issue. Dollars can buy a lot of R, depends on your needs.

Posted By buddy on 28 Mar 2010 05:20 PM
I am still looking for windows and another site raves about them as the absolute best...I haven't read anything here to reaffirm....Thoughts?

Two things to consider - frame material & glazing.  I think fiberglass is the best choice for window frames, but it is definitely more expensive  Fiberglass is good because it doesn't expand & contract with temp changes like a vinyl window will do.  Over time, that equates to less stress on your seals. 

As far as glazing, it really depends on the situation.  u-values & SHGC values are always a tradeoff, and depending on where you're located, how your house is oriented, etc., will all affect what makes the most sense.  A high solar heat gain window will have a higher u-value, but in some climates it makes sense, because you'll gain more heat from the sun than you'll lose from inside.  If you're in a warmer climate, you want to block out as much of that outside heat as possible, so the low u-value becomes more important.

Marvin' s lowest U value is a .29, DP is 35 and air infiltration of .27. The numbers are not impressive when compared to other fiberglass windows. But I have to admit, it is a pretty window.....

The Milgard Ultra series is a similar fiberglass window, a little less expensive from the dealer I talked to, comes with nicer divided lites. Find a way to like casements or awning windows and get the better sealing.