I'm working on an apartment building and trying to figure out what my
baseline should be. For the residential units, the proposed building is
split system heat pumps and supplemental electrical. So for the baseline
I'm using PTHPs. For the retail and other non-residential areas which are
mostly on one floor, the heating is electric so I'm using System #4.

The confusing piece to me is an outside air unit serving the corridors of
the residential area. It has a gas-fired furnace that is heating the air to
70degF. It is the only fossil fuel device in the building and I'm not sure
that the baseline should be hybrid for this. I have a feeling that a hybrid
baseline will hurt me.

Has anyone done anything similar in the past? What has worked for the LEED
reviewers?

Thanks in advance.