16 years ago Jim Larsen taught us the basics of window and glass performance. After 40 years in the glass business – you might have heard about his company…Cardinal Glass Industries… he will present “the rest of the story”….”how windows actually affect building performance”. Jim will present the results of a huge research project with Oak Ridge National Laboratory. It only took 500,000 computer runs and judgement from a few legends to refine our understanding. I view this body of work as “unprecedented” and I mean that in a good way. Jim will introduce us to “unobtanium” and windows 2100.