EnergyGauge Support Center

I think I need some help.  I have a house where, when I run the computation for the HERS rating it comes out as an 83.  When I run it as HERS IAF it comes out at 107.  24 seems like a HUGE adjustment for the size of the home.  I've run HERS vs HERS IAF on a few other projects and they were typically pretty close to one another.  Within just a few points.  Granted, this is one of the bigger homes I see (its 3716 sq ft) but the difference in 24 points seems way out of proportion.  Any ideas, suggestions?