Market Intelligence

Commissioning the Green Building

Commissioning the Green Building

There is the potential for installation and operations problems in all newly constructed buildings. Green buildings may include special systems and equipment that are not familiar to the owner, maintenance staff, or some members of the design and construction team. Consulting an independent, qualified commissioning agent during the programming phase can save time and money and, perhaps most important, ensure that the building functions properly and is easy to maintain and operate as designed.

Commissioning is often thought of as a series of tests conducted on equipment prior to the turnover of systems to the building owner at the end of a construction project, but final testing of systems is only one aspect of commissioning a building. ASHRAE defines commissioning as the process of ensuring that systems are designed, installed, functionally tested, and capable of being operated and maintained to conform to the design intent. The process begins with planning and includes design, construction, start-up, acceptance, and training, and can be applied throughout the life of the building.

There are a number of commissioning resources available that employ different methods of accomplishing the same goal—providing a building that operates as intended—with full documentation and training on all systems. The sources that are referred to most often by owners and commissioning providers are:

Portland Energy Conservation Incorporated (PECI)

California Commissioning Guides (2006 available online for free)

—New Buildings

—Existing Buildings

California Commissioning Collaborative – Retrocommissioning Tool Kit (2007/2008 available online for free)

ASHRAE

Guideline 0-2005–The Commissioning Process

Guideline 1.1-2007–HVAC&R Technical Requirements for the Commissioning Process

Building Commissioning Association

Building Commissioning Handbook, 2nd Edition

SMACNA

HVAC Systems Commissioning Manual, 1st Ed., 1994

Not all aspects of each of these guidelines are required. Owners may choose to have the commissioning agent perform some of these activities and eliminate others. Not surprisingly, cost is the primary reason for reducing the commissioning scope, although it can be argued that the less thorough the commissioning, the higher the costs will be in change orders, energy consumption, and maintenance over the life of the building.

LEED® 2009 for new construction and major renovations includes two levels of commissioning: fundamental and enhanced.

These basic commissioning activities are prerequisites to achieving any rating:

Engage an independent Commissioning Authority (CxA) with documented experience on at least two projects. (For projects under 50,000 sq. ft., the CxA may be part of the design team.)

The CxA must report results directly to the owner.

The CxA is to collect and review the owner’s project requirements and basis of design documentation.

Develop and include commissioning requirements in the construction documents.

Develop and implement a commissioning plan.

Verify the installation and performance for each commissioned system.

Complete a summary commissioning report.

The commissioning process must be completed for the following energy-related systems:

Heating, ventilating, air conditioning and refrigeration systems, and associated controls

Lighting and daylighting controls

Domestic hot water systems

Renewable energy systems (e.g., wind, solar)

To receive two extra points for commissioning (enhanced commissioning), the following additional activities must be performed:

Prior to the construction documents phase, designate an independent CxA.

Conduct at least one focused review of the design prior to the mid-construction documents phase, and back-check the review comments in the subsequent design submission.

Conduct a selective review of contractor equipment submittal documents for equipment to be commissioned. Perform the review concurrently with the design engineer.

Develop a systems manual which provides future operating staff with the information required to understand and optimally operate the commissioned systems.

Verify that the training requirements for the project have been completed.

Review the operation of the building with operations staff within 10 months of substantial completion. Include a plan for resolving outstanding commissioning-related issues.

Consult the LEED Reference Guide for Green Building Design and Construction, 2009 edition for detailed guidance on the rigor expected for design and submittal reviews and creation of the systems manual.

Commissioning tasks should be structured to meet the requirements of the project, and not just the points for a rating system. The more complex the components and systems, the more detailed the commissioning effort should be. For all projects that utilize the sustainable design approach, the commissioning agent should be hired during the programming phase so that he or she can provide input and help define what the building should and should not be able to do. In this way, attributes that may be deemed desirable by some may be negated by the commissioning agent prior to the design team spending any time incorporating these features into the design. Hiring the commissioning agent at this early stage of the process will provide the greatest benefit to the owner.

Arthur Adler, PE, CEM, author of this article, is principal of Applied Energy Engineering & Commissioning located in Manchester, Massachusetts. This article is adapted from Green Building: Project Planning & Cost Estimating, 3rd Edition, available through RSMeans.