specific mechanical drawings for PI4?

The main role of the overview documents is to help the reviewers understand the context of the whole project and systems since individual credits are often reviewed by different people. Since they may not see the documentation for other credits, you can minimize misunderstanding and off-base requests for clarification by providing good background information. For mechanical sheets, usually the overall plan sheets rather than details or enlarged plans are sufficient.

Is everyone taking it to just mean the HVAC dwgs (piping & ducts), and not the electrical, plumbing, etc? Same goes for the mechanical schedules - include just the HVAC schedules, or schedules for all MEP items? Since it asks for a narrative describing all the systems, it makes me wonder what they mean by "mechanical".

Renee,

Yes, the HVAC drawings for piping & ducts are the mechanical drawings for this area of LEED Online. You'll need to provide lighting drawings if you're pursuing SSc8 or EQc6.1, and a plumbing fixture schedule for WEp1.

If that is the case, I find it strange that the individual credit/template doesn't ask for those specific dwgs, or that at least the PI 4 directions don't clarify what to upload (if going for this credit, upload this information). Thanks for the info - I will add in the elec dwgs with the mechanical, and the plumbing schedule with the mech schedule (probably the elect one too, for good measure).

Renee, I'm sorry if my response was confusing. If you're pursuing SSc8, you would upload the lighting drawings under the SSc8 required uploads section, not under PIf4.