Common schedule for VAV zones with differing occupancies?

Ok so for the thermostat/fan schedule, it's as simple as making one schedule that encompasses all of the hours of the year that any one of the zones is to be occupied? What about when you have a zone, such as an attic where you don't care if it gets very warm, and you want to set the thermostat for something much higher than the required "supply air temp + 20 degrees" range? If you set it to the normal value (75 degrees let's say) along with all the other zones, you may get excessive unmet load hours in the Attic zone. Is it better to do this and then explain why the unmet load hours are high, or in this case should you break away from the "supply air temp + 20 degrees" rule and set the thermostat for that particular zone to the higher designed setpoint (i.e.; 90 degrees)?

The attic is occasionally occupied. It's a storage room and mechanical room and the only cooling/ventilation is done with exhaust and pulling outdoor air through, either when the room is occupied or when the thermostat calls for cooling. But my point is that it's on a VAV system with a bunch of other zones. The supply air temperature is set to 55 degrees, because all of the other zones are at a 75 degree thermostat setpoint. But this Attic zone has a 90 degree thermostat setpoint in the proposed design.

The attic does have its own system (in the proposed design). Are you saying I'm allowed to model it as its own system in the baseline building as well? And under what exception is it allowed, for future reference? For reference, it's currently being modeled along with all of the other spaces on that floor, as they all are minimally occupied (0-4 hours per week). Thanks.

Thanks!

One more clarification I want to make regarding the schedules of a baseline VAV system with several zones of differing occupancy vs the schedules of several single zone units for the proposed building: The schedules have to be identical from Proposed to Baseline: thus the occupancy schedule of a space in the proposed building must match that of the baseline building. But what about the Fan/Controls schedule? If your proposed building is a bunch of single zone systems with unique operating hours and your baseline building is a single VAV system with multiple zones you're gonna have one baseline fan schedule and several proposed fan schedules. In other words, let's say my proposed building has two single zone RTUs serving an office area and a multipurpose area respectively. The two spaces have very different operating schedules, but are to be grouped together as a single VAV system with two zones in the baseline building. I will match the occupancy schedules of the spaces in the baseline to the proposed. But I'm only going to have one fan schedule for the baseline system (since it's a single VAV unit), while I'm going to have two unique fan schedules for the two separate proposed single zone units. Is that acceptable or do I have to create a single proposed fan schedule that accounts for all occupied hours between the two systems to match the single baseline fan schedule? I'm guessing not, but just want to be clear of how strict is "the schedules must be identical for the baseline and proposed buildings". Thanks.

Ok, thanks for the suggestions. Seems like this would be a common issue. I'm surprised Appendix G doesn't spell it out better. In the situation I'm describing, the hours vary by far less than 40 hours per week. It's more like one space is open on Monday in the morning for 4 hours and the other space is open on Wednesday night for 3 hours. And then both are unoccupied the rest of the week. If they were similar hours I could see adjusting them both to be the same, but in this case, that would impact solar loading and demand charges. Is there ever application where you can have multiple VAV systems on the same floor for the baseline? Or is the "one VAV system per floor" rule an absolute?

Understood. Thanks!

One more clarification, please. If I deem it necessary to model more than one VAV system per floor for the baseline, because my proposed design has some exceptional systems, Do I model the exceptional VAV systems with non-reheat VAV boxes and gas furnaces, or do I model them with reheat VAV boxes and a hot water boiler? And if I model the exceptions with the hot water heat, do I make that boiler/plant separate from that of the primary baseline VAV system?

What if the area I'm formally taking exception 'b' for is served by a multi-zone packaged VAV system? Do I have to model each zone of that area with a separate single zone packaged unit with gas furnace heat (system 3) or should I use a single packaged VAV system with hot water reheat (system 5) like the rest of the baseline building?

Testing.... not sure if my reply posted.