400 would kind of be below the Marvin Ultima and wood Ultrex . The 400 Woodwright would be above the wood Ultrex and below Ultima. I'd consider both Andersens to be above the Marvun all Ultrex , but it is an another class of window. The Andersens do not feature aluminum or fiberglass in those lines, they are painted wood and Fibrex. Performance wise they are all very similar in U values and DP ratings, air infiltration numbers on the Andersens are very good, Marvins are known to be poor but I haven't seen any first hand ratings. Price wise should be in this order but may not be: Ultima, 400 Woodwright,Wood Ultrex, 400 , All Ultrex. I am not to familiar with Kolbe's line up.

So, your double pane U-Factor appears to be a 0.27. Good, but what about that "will add thermal performance that far exceeds the vinyl options". I am quoting you directly from above about 6 posts ago. There are more than a handful of vinyl windows that will best that thermal performance in the case of double pane and more than a handful that equal or best the thermal performance numbers that you show in triple pane. To be certain, 0.15 is a good U-Factor, but it is only equivalent in this case to just the handful of vinyl windows that I know of personally not to mention the more exotics that are designed solely around performance. I do love nice wood windows, but to claim they are more efficient because of the wood is sketchy science to put it mildly.

Post up a picture. Its likely a design error in the mechanism of how the operable sections interface with the frame. We call those drafts "chimney" drafts when they go up the balance/jamb slots. Lets see a picture of the window and with it tilted in. You can likely install some foam blockers in the channels to help with the drafts.

Thanks, Sharon. Our budget is pretty small -- we are basically building on a shoestring here -- and I think we have done the best with what we can afford (but we're certainly not pros at this!). However, it is a full walkout on the side with the door, and the elevation on the front and rear slope down, like the sides on the house you show. The elevation drawings I included aren't up to date with the most recent grading plan. It's a little less conventional but fits our desire for a south facing long side of the house as well as the current elevation of the site. The reason we were trying to avoid the beam is because our foundation guy told me that we can't have a beam sitting over the door for structural reasons. We are doing a pre-cast (Superior) wall for the foundation.