Thanks, Carol, for your quick response. I think my question might have
been too specific. My baseline model agrees to within 5% of the actual
gas and electric bills for the building. The exterior walls, especially
north and south elevations, are about 30% windows by area. By replacing
single-paned windows with double-paned, modern windows, I am expecting
about a 23% reduction in energy usage based on simple heat equation
estimations. eQuest is only returning a 5% savings. I suspect I am not
defining the replacement windows correctly, but it seems there must also
be a problem with how eQuest is calculating my heating loads through the
windows. I specified the windows' estimated percent wall area, and also
drew custom windows everywhere to match what the actual building looks
like. What is the best way to approach solving this problem?

Thanks again,
Ben