The drive toward high performance buildings demands the integration of diverse building systems that were not previously required to interact with one another. For example, occupancy sensors no longer control just lighting in a space. They also control the HVAC system supplying that space. When a worker leaves the office, not only does the occupancy sensor turn off the lights, it sends a signal that throttles down the variable-air-volume (VAV) box serving the office to its preset minimum.
This example of the integration of the building lighting and HVAC system serving a particular room or area through a shared sensor is becoming increasingly common in today’s commercial and institutional buildings. Controls are the key to integrated building systems (IBS) and to reconciling the seemingly conflicting goals of increasing both building operating efficiency and occupant comfort simultaneously.
However, from a design standpoint, the integration of diverse building systems becomes very difficult to specify using traditional descriptive and prescriptive specifications because of differences in control device and system characteristics, options and operation. Increasingly, consulting engineers use performance specifications for IBS, and this provides new opportunities for electrical contractors (ECs).
A performance specification defines the performance requirements for a particular type of equipment or system. It is the EC’s responsibility to select the equipment or design the system needed to achieve the contractual performance requirements, procure necessary materials and equipment, install the equipment or system, and verify its functionality. A performance specification is an opportunity for the electrical contracting firm to showcase its technical knowledge and expertise and provide the owner with the equipment or system that meets its needs. In addition, a performance specification allows the electrical contracting firm to select materials and equipment that meet the contractual performance requirements and allow the electrical contracting firm to select manufacturers and suppliers that provide the best combination of price, delivery and service.
The advantages of performance specifications do not outweigh increased risk for the EC. With traditional descriptive and prescriptive specifications, the electrical contracting firm only had to purchase materials and equipment that met the technical specs and install them in accordance with the contract documents. Responsibility for equipment or system performance remains with the owner under a traditional descriptive or prescriptive specification.
If the EC procured and installed the equipment or system in accordance with the contract documents and performance fell short of the owner’s expectations, then the owner would need to turn to its consulting engineer for the fix. In this case, the EC should receive a change order for any additional work required to modify or replace the installed equipment or system. Under a performance specification, however, if the equipment or system does not meet the contractual performance requirements, then it is the contractor’s responsibility to fix the installation for no additional time or money.
The key to controlling performance risk associated with an IBS performance specification is to thoroughly understand the owner’s requirements. They may be explicitly stated in the specification as measurable operational characteristics or performance criteria. The performance requirements also may be implicitly included in the specification by reference to codes, standards or green building rating systems.
The electrical contractor also needs to make sure the performance criteria in the specification can be met with current technology. In the past, ECs have gotten into trouble by assuming, since the criteria could not be met by current off-the-shelf technology or that the owner really didn’t need the level of performance specified, they would not be held to the specification requirements. Electrical contractors should always request a clarification prior to submitting their bid or proposal to avoid problems at the end of the project.
If the specification does not include measurable performance requirements, the EC must develop his own criteria and include it as part of the bid or proposal and, eventually, as part of the contract. Wherever possible, performance requirements should be based on industry codes and standards, especially when the outcome may be subjective, such as in the case of illumination levels and visual comfort. In this case, look to Illuminating Engineering Society standards and recommended practices for measurable criteria. Always define subjective IBS performance specification adjectives, such as “the best,” “adequate” or “state-of-the-art” in a bid or proposal, using measurable performance criteria. After the contract is signed, it is too late to further define the terms, and these subjective terms often provide ground for disagreements and disputes at the end of the project. EC
This article is the result of a research project investigating the emerging IBS market for the electrical contractor that is being sponsored ELECTRI International (EI). The author would like to thank EI for its support.
GLAVINICH is an associate professor in the Department of Civil, Environmental and Architectural Engineering at the University of Kansas. He can be reached at 785.864.3435 or email@example.com.