I am working on a project in which we are trying to get the full tax
incentive of $1.80/sf. The lighting and envelope are pretty easy to
figure, but I'm confused on the heating and cooling portion. You have
to be 20% less than ASHRAE 90.1. Well I have modeled the building in
eQuest with the units we used and again with the units ASHRAE 90.1
recommends for the baseline. Do I need to be 20% lower than the gas and
electrical demands, or a combined 20% between the two. Thanks for your
help.

Matt McCalla, P.E.