Wednesday 12 June 2013

A Case Study on Total Building Commissioning: U.S. District Courthouse in Salt Lake City


Introduction
Principles and procedures of Total Building Commissioning (Cx) are presented as a case study of the U.S. District Courthouse, which is being constructed in Salt Lake City, Utah, USA, as a design-bid-build project.  This 10-story building has a floor area of approximately 357,000 gross square feet and has an estimated construction cost of $177 million. The construction is to be completed in July 2014. Setty performed total building commissioning to Commissioning (C x) to evaluate the integrated performance of building systems.

The new courthouse was designed in accordance with the PBS Facilities Standards P100-2005 and the 2007 U.S. Court Design Guide.  It has also  been  designed  to  achieve  “gold certification”  in  accordance  with Leadership  in  Energy  and  Environmental  Design (LEED®),  which, through  its  requirement  for  commissioning,  is  intended  to  verify that  the building  has  been  designed  and  built  using  strategies  aimed  at improving overall performance compared to a baseline design. 

This case study  focuses  on  commissioning  of  several  systems  during  the  design  phase,  and partial commissioning of the envelope system, which was the only system available for  performance  testing  during  the  early  stage  of  construction. Findings and conclusions are presented regarding performance enhancements of several systems attributable to commissioning during the design phase, and performance testing of the envelope system during the early construction stage.

Conclusions
1)  Successful Total Building Commissioning (C x ) is highly dependent on the clarity and timeliness of the criteria and procedures that are defined in the Owner’s Project Requirements (OPR).  The 10-year gap  from  start  of  initial  design  to  start  of  construction  was  an impediment to the C x  process in this case study.
2)  C x is more than a design process.  Commissioning of the physical systems to pre-set criteria at the onset and duration of construction is critical to successful building performance.