The following news article was printed in the Winter 2001 issue of The Balance Sheet, the newsletter of the National Environmental Balancing Bureau (NEBB) and reproduced with their permission.

Discipline Spotlight: Building Systems Commissioning
University of North Dakota and Building System Commissioning

The University of North Dakota - Facilities Department, Environmental Engineering, and EAPC (a local engineering firm) of Grand Forks, North Dakota, developed Building Commissioning Procedures in the early 1990’s after it became apparent that the Design - Bid - Build form of construction was not delivering end results that the University of North Dakota (UND) desired.

Prior to 1990, it was quite common for the Facilities Department to spend up to two years and go through two complete heating and cooling seasons before all heating and cooling issues were corrected. On multiple occasions we retained the services of Environmental Engineering (a NEBB contractor) to verify the work other balancing contractors had done and to help us determine problem areas. In many cases, prior to using NEBB firms, it became apparent that test and balance (TAB) work was not performed to the level of quality needed to identify problems that prevented building HVAC systems from operating properly. It was common to find problems with the original design, installation, startup, and maintenance issues after a building was constructed. Even though most of the design, specification, and construction problems were eventually solved, UND Facilities (the owner) would have to absorb these costs. Building occupant complaints during this two-year period also were excessive.

We realized that a different approach to HVAC construction projects had to be developed.

Environmental Engineering proposed, and UND and EAPC adopted, a four part process to improve the design and construction process on larger projects.

Phase I

The Commissioning process starts with a review of the project during the design phase. The purpose of this review is to spot problems that would prevent the HVAC systems and buildings from operating properly. This review begins early in the design stages and is done before the bid process is complete. The commissioning review checks for acceptable velocities in pipes, ducts, coils, equipment and registers. System Effect on fans is also evaluated. Duct and piping, details and specifications are also reviewed to assure that proper installation

techniques are written and detailed in the plans and specifications. This review process has greatly reduced design problems that show up during startup and are either impossible, or costly, to fix after the fact.

It is important to engage the building system commissioning (BSC) team member early in the design phase. UND initially started the design review after the project was bid. This caused a confrontational relationship to develop between the design professional and the BSC firm. Changes made to the design after the project was bid also caused costly change orders to be generated.

Bringing the owner, design team and the BSC together during the design phase has eliminated this stumbling block. The engineering firm is also given the review guidelines to follow before the design begins. This review gets the entire team involved so that all concerns are addressed before the project is bid.

Phase II

The second phase of the BSC process involves weekly or biweekly inspections of the duct, piping systems and equipment installation. The purpose of this inspection is to insure that the details and specifications outlined in the design process are followed.

It is important to have a pre-construction meeting with the engineer, owner’s representative, BSC agent and the Mechanical and HVAC contractors. The purpose of this meeting is to discuss the inspection process and to show the mechanical contractor details and specifications that will be inspected. Once the contractors understand the methods that will cause a test to pass or fail, their work is usually performed in a manner that allows tests to be passed.

Phase III

Phase III involves the startup of equipment and the testing adjusting and balancing of the mechanical systems. Although the Mechanical contractor is responsible for the startup of all equipment, UND observes and monitors all startups.

Test and Balancing of all mechanical systems starts once all equipment and controls have been started and are running. UND spot-checks final TAB readings for accuracy. When TAB firms realize that we are serious about the quality and accuracy of TAB test readings, balance problems were reduced.

UND has found it beneficial to bid and issue separate contracts for test and balance work. This gives UND more control over the firm selected and does not put the TAB contractor under the control of the Mechanical Contractor that is being inspected.

We have also placed a NEBB-only inclusion in our TAB specifications. The NEBB qualification, separate contract, and random spot-checking have significantly reduced the times that non-qualified TAB firms are selected to work for UND. Building systems are now set up according to design requirements.

Phase IV

The fourth phase of the commissioning process involves a complete check out of the control system, a verification of control loop operation, and a point-to-point check of all control points. Facilities personnel from UND and the control contractor perform these tests to insure proper operation.

Once this phase of the process has been completed, final O & M instructions are given with the BSC, TAB, control and mechanical contractors giving individual lessons on the system operation.

While it may seem that this is a long and involved process we have the following results to show for it:

Commissioning works. However, it is not a process that begins after construction is complete. It starts before bid day during the design process and runs through the entire project. It is impossible to successfully operate a building that has inherent design or installation problems buried within the completed building structure.

When commissioning is performed using a team approach, time and money are saved, a superior product is produced, and the aggravation experienced at project completion is reduced substantially. Building owners can be assured that the mechanical systems are operating as designed and at peak efficiency. This process benefits the contractors as well by enabling delivery of a refined product helping to eliminate costly callbacks to the job site after construction is complete.