I am working on a BD+C: Healthcare project that is a new building addition adjacent to an existing hospital. As this building is being designed for possible vertical expansion in the future, we are not placing the chillers that serve the building on top of its roof. We plan on locating the chillers that are dedicated to this addition on the roof of a separate (non-certified) building several buildings away.

In this situation, do we need to include the area of the roof where the chillers are placed within our LEED site boundary drawing? We plan on including these chillers in mechanical systems and energy-related calculations/credits as they directly serve our addition and our addition alone, but we are unsure if that roof area needs to be shown as an "island" that is part of our LEED boundary.