Hey all,

I'm about to begin a LEED energy model for a warehouse project that contains a very large process load. It will be a major renovation project. The building will be broken out as 50,000 sq ft office and 300,000 sq ft warehouse. The anticipated HVAC systems on the project are package rooftop units with DX cooling/gas heating for both the office and warehouse areas. The warehouse space requires cooling and heating.

Two issues that come to light:

1. Large Process Load

a. Anticipated process load will consume roughly 40-60% of the buildings annual energy consumption. The Exceptional calculation method has been considered. However, the process being done at this facility is extraordinary and there is not a "baseline" to compare savings off of.

2. Baseline System

a. Based on the size of the warehouse, System 7 will be modeled. This system is a packaged rooftop VAV with reheat with chilled water and hot water boiler system. Based on previous experience and preliminary modeling results, the baseline system will be more energy efficient than the package rooftop units with DX cooling/gas heating. There's been a suggestion by our team to request a LEED Interpretation and to possible change the baseline system to also packaged rooftop units with DX cooling/gas heating as that is typically designed for warehouse type facilities.

Based on these two issues, I am having a hard time foreseeing this project being able to hit the minimum 5% savings requirement on major renovations. I searched the LEED Interpretations database but didn't find one that dealt with a project that had both these issues.

Any suggestions?

William Mak, LEED AP BD+C