Class A office building system design: Codes and standards

Class A office buildings are among the toughest projects an engineer can work on—complex structures, demanding clients, and advanced technology. Codes and standards dictate many of the design parameters.

By Consulting-Specifying Engineer February 24, 2016


Daniel G. Dowell, VP Energy Performance Contracting Sales, ABM, Raleigh-Durham, N.C.

Kurt Karnatz, PE, CEM, HBDP, HFDP, LEED AP, President, ESD, Chicago

Lance Kempf, PE, Director of Mechanical and Electrical Engineering, LEO A DALY, Minneapolis

Brian Michelson, PE, MEP Design Phase Manager, Mortenson Construction, Minneapolis

Joseph H. Talbert, PE, ARM, Project Manager, Aon Fire Protection Engineering, Lincolnshire, Ill. 

CSE: Please explain some of the codes, standards, and guidelines you use as a guide when designing Class A office building facilities.

Talbert: The International Building Code (IBC) is the most commonly used code for designing Class A offices in the U.S. In many other countries, the IBC may be used to provide guidance for code issues that are not defined by local country codes or where, in the judgment of the design professional, the local country code is not considered to provide a high enough level of life safety. Similarly, NFPA 101: Life Safety Code may be used to supplement local code requirements for means of egress.

Kempf: Although the specific codes affecting building system engineering change from city to city, state to state, and country to country, each project requires research and a working understanding of all applicable building codes and system/construction standards.

Michelson: I’m constantly referencing ASHRAE 62.1 during the design process. I typically review the local and state plumbing, mechanical, energy, fire, and building codes to make sure I’m not making assumptions. It’s always a challenge when working in different jurisdictions because they all have their own approach to the codes. Plumbing codes seem to vary the most around the country.

CSE: How have International Building Code, NFPA, ASHRAE, and other codes affected your work on Class A office building projects? What are some positive/negative aspects of these guides?

Michelson: The codes haven’t had a major impact on work effort unless the project is a high-rise or a mixed-use development. High-rises are a challenge to implement smoke-management systems that have to interface with HVAC equipment operation during emergencies. As the codes have changed over the years, they have forced construction costs to increase to meet the new standards. It is frustrating when the code changes result in greater expenditures for marginal improvements in energy savings or safety.

Talbert: The IBC, local building codes, and NFPA standards are positive in that they provide a baseline of standards that are widely adopted and accepted. In addition, the IBC and NFPA have provisions that allow the use of PBD, which can be used to demonstrate that an acceptable level of life safety has been achieved for conditions that may not be code-compliant. This allows greater flexibility for the designer.

CSE: What international codes pose challenges as you design Class A office buildings outside the United States?

Talbert: One of the greatest challenges in designing Class A office buildings outside the U.S. is that translations from the language of the code into U.S. language are often difficult to understand because of difficulties in translating technical language that, although well-understood in the language of origin, has no direct counterpart in the English language. For this reason, it is essential to have members on the team who are fluent in each language and who have knowledge of the technical terms used in both languages so that it is possible to develop a coherent, understandable design.