Interior renovation within a single tenant building

If there is no parking designated for the radiology suite, it seems like the conservative approach here (and LEED usually smiles on conservative approaches) would be to follow Case 2 and approach this credit as if you were the whole hospital. But if that approach seems problematic to you, I would check with GBCI. If you do that, please report back what you learn.

It seems that the appropriate approach to the credit would be to follow Case 1, Option 1. Although the parking area is shared, the project team should still be able to quantify the number of tenant occupants, then designate the appropriate number of preferred parking spaces in the parking area based on that number. While this may be difficult because there are no spaces designated to individual programming spaces in the hospital, consider working with the building management to designate the appropriate number of spaces for your project. At some level the parking is designed to meet the needs of the hospital's occupants, so the team should be able to drill this down and determine a number of spaces for the clinic. If this isn't feasible and there is no way to designate spaces for the clinic, this credit may not apply to your project. However, as the previous comment suggests, follow-up with the GBCI to confirm your approach.

This credit is quite a challenge for hospitals in general, because there are often requirements or recommendations unrelated to local codes which cause a hospital to install more parking than they might if they took the code literally. Regardless of the option selected, if your sense is that a significant amount of the campus population uses transit, then you should follow through with this credit; otherwise it's less likely that the hospital will have a parking capacity at or below code minimum.

You may want to ask your client if they have done a formal parking study in recent years unrelated to your project -- this will tell you the source and justification of parking numbers. In my region, one common practice is to use local code to determine parking requirements for MOBs, but ITE values for inpatient square footage.

To follow-up, It may also be possible for the radiology suite project to use an FTE approach to determine the number of preferred parking spaces. As noted in the CIR below, the USGBC has recommended this approach for past campus projects with shared parking facilities. Although old CIRs cannot be referenced for v2009 compliance, they are good to look to for general guidance. It may be worth contacting your project’s Certification Body (CB) to ensure this approach meets the requirements.

5/25/2008 - Ruling
The project is seeking clarification on how to determine the number of parking spaces allocated as preferred parking for low-emitting and fuel-efficient vehicles, for a building with shared parking on a multi-building campus. The proposed calculation methodology of using Full Time Equivalent (FTE) numbers and providing 5% of the FTE number with preferred parking is acceptable for this credit. As this is a campus project, preferred parking can be provided in the existing multi-level parking structure, even though it is not a part of the LEED Project Boundary. The skywalk and pavilion, which are additions to an existing building, can also be excluded from the LEED Project Boundary.