I have been brought into this project as the LEED consultant at a very late stage (about to start construction).  

This is the third phase of a large college science facility.  This is an addition which includes classrooms, labs, and several small greenhouses.  There was no energy model for this phase because there is no head-end equipment or Mechanical room in this section of the facility.  That was all built (and modelled) in the previous 2 phases.  All new ductwork/piping/etc. is being connected back into now-existing Mechanical rooms located in the previous phase. 

So, I am trying to figure out how to earn this PR.  I have never dealt with this scenario before.  Is the only option to tell them they need to model this phase?  Is this a brand new model, or a revision of the previous one (to include this additional square footage)?

Unless I am missing something, I do not think that either of the prescriptive paths is possible.  This is the smallest of the phases in terms of size, but it exceeds the 20,000SF limit for Option 2 (and isn't the right project type).  Option 3 doesn't apply because this phase contains labs.

Thoughts?