In any sustainable construction job, the project team is focused on the final stage of the project – construction closeout – long before the building is completed. This fourth, and final segment, to our “Contractor’s Role in Sustainability” series focuses on the benefits of this proactive approach.
At the completion of any sustainable construction project, that project enters the construction closeout phase. This phase involves a series of steps that represent the coordinated closeout of the LEED project, leading to the submission of LEED construction credit documentation and deferred design credit documentation for review.
A LEED project validation team must verify the accuracy of the information submitted; assure that documentation claims are verifiable; and confirm that products and materials were actually installed. The team is also responsible for ensuring that the contractor and subcontractors are prepared for building flush-out and have compiled all necessary LEED documentation requirements.
It’s a big job, and one that starts long before the project is completed. The contractor is a key player in the construction closeout phase, as well as the previous phases of a sustainable construction project: predesign and design and construction.
Building Commissioning – The Importance of the Contractor
In order to comply with the requirements of the Energy and Atmosphere (EA) Prerequisite 1: Fundamental Commissioning, a Commissioning agent (CxA) will verify that the building’s energy-related systems and equipment are installed, calibrated and perform per specifications. The CxA will also ensure that the systems satisfy the owner’s project requirements (OPR), basis of design (BOD) and construction documents.
The process for verifying that these systems perform as designed, built, operated and maintained per OPR, according to LEED standards, is called commissioning. Fundamental Commissioning is a prerequisite for all LEED projects.
Projects may earn two LEED points for enhanced commissioning. The CxA must have documented commissioning authority experience in at least two building projects. Under the current rating system (LEED 2009 or v3.0) if the building area is less than 50,000 square feet, the CXA could be a member of project team with design or construction responsibilities, but they must be independent for projects bigger than 50,000 square feet.
Commissioning must be completed for the following energy-related systems, at a minimum:
- Heating, ventilating, air conditioning and refrigeration (HVAC&R) systems
- Lighting and day lighting controls
- Domestic hot water systems
- Renewable energy systems (e.g., wind, solar)
Prior to building occupancy, the CxA shall verify the performance of energy consuming systems and complete a commissioning report with recommendations or action items that needs to be performed by the contractor prior to accepting the commissioned systems.
The contractor assists the Commissioning Agent by accompanying him or her on walk-throughs, answering questions and performing system tests. The LEED project could earn two points under enhanced commissioning by achieving the following:
- The CxA or the contractor must develop a systems manual for all commissioned systems.
- The CxA or the contractor must verify that the requirements for training operating personnel and building occupants have been completed.
- The CxA must review the operation of the building within 10 months after substantial completion of the project.
Though building envelope commissioning is not a requirement under the prerequisite or credit, the project may earn one point under innovation and design.
Indoor Air Quality Management: Building Flush-out Before Occupancy
Before building occupancy, the contractor will conduct a building flush-out to ensure that air contaminants from construction are removed. Typically, the mechanical systems are run for two weeks minimum, using tempered 100% outside air and Minimum Efficiency Reporting Value (MERV) 13 filtration media. Once flush-out is complete, the filters should be replaced.