I understand fire station has residential spaces.  Under 90.1, it requires residential to use PTAC #1 for system type.  Due to having gas available, is it correct to model the baseline system PTAC for air conditioner and fossil fuel boiler?  It would not make sense to have to model a gas boiler for a residential application with less than 20,000 SF as that would not be practical in most any installation.  Because of the limitation of one system type for small SF, we are not allowed to use 2 system types.  The PTHP or PSZ-AC options would be a much better direct application for a commercial fire station with some small sleeping rooms.  Any interpretation to classify as non residential, 3 floors or less and less than 25,000SF when fire station is occupied 24/7?