Hello there.

We have a project that will be applying for LEED certification under CI. The project is located on 4th floor within an office building with 5-floors. The building is served by a common HVAC system: air cooled chillers. We have the following doubts for EAc1.3 using the option # 2-ASHRAE APPENDIX 11:

- Is it necessary to simulate the whole building? The LEED Guide for ID+C indicates that the building segment served by the common HVAC system must be simulated (in this case, the whole building). We think that simulating the whole building is impractical.

- If we have to simulate just the floor that is under certification, how do we model the HVAC system in the design model? The chilled water is metered and billed separately for each tenant within the building.

How do we assign the system type in the baseline case model?

- Marcus, in other comment you wrote:

“Having to model the whole building with a central plant is a major problem for the project we are working on. We wrote a CIR many years ago which was approved for NC where we proportioned the load on a central plant to model an addition. The same methodology could be applied for a CI space IMO.

The biggest problem is often determining the existing conditions beyond your scope especially in multi-tenant spaces.”

Can you tell us the CIR number so that we can look for it and try to understand this manner in a better way?

Thanks in advance.