Hello!

An educational building will have no AA for its classroom, workshops and labs (mainly 90% of the project area), as all these areas will be naturally ventilated (complying with section 5.1 of ASHRAE 62.1-2007). I'm going to make the energy model for this project, so I've reading the "ANSI/ASHRAE /IES Standard 90.1-2010 Performance Rating Method Reference Manual" prepared for the US DOE (cited before here if I'm not mistaken), it says: "In the case when the thermal zone does not have a cooling system: The thermal zone in the proposed design is modeled with no cooling when the natural ventilation system maintains temperature. For periods when the space temperature is greater than the cooling setpoint, a cooling system like the one for the baseline building is assumed to operate to maintain temperature. The fans in this simulated system cycle with loads. The corresponding thermal zone in the baseline building is not modeled with natural ventilation. The baseline building HVAC system, as defined in Standard 90.1-2010, Section G3.1.1 (Table 1 and Table 2 of this document), provides cooling to maintain thermostat setpoint.".

1. Is this approach also valid if using version 2007 of ASHRAE 90.1?
2. Just to make sure what Baseline system (from table G3.1.1A) should I use; it's an eleven-story building, but the conditioned area is less than 14000 square meters (just some offices), so is it ok System 8?

Many thanks in advance.