The challenge: Tall and super-tall buildings: Codes and standards
High-rise buildings aren’t just big—for engineers, they present big challenges. Meeting building codes and standards becomes a new challenge in these cutting-edge structures, both in the United States and abroad.
Jason Heffelmire, PE Gulf Coast operations director, TLC Engineering for Architecture, Tampa, Fla.
Mehdi Jalayerian, Executive vice president, Environmental Systems Design, Chicago, Ill.
Jim Quiter, PE, FSFPE, LEED AP, Principal, Arup, San Francisco, Calif.
CSE: What codes, standards, or guidelines do you use as a guide as you work on these facilities?
Jalayerian: Stretching buildings to greater heights generally means there are no codes that describe exact applications for these buildings. For this reason, one responsibility of the design team is to work with local authorities to create a better understanding of how building systems for these towers need to work and how the latest international code models can be taken to the next level and made applicable to new projects. New super-tall buildings incorporate best internationally recognized building codes and design/construction practices while anticipating subsequent local code changes.
Quiter: Regardless of where you work in the world, there are minimum codes and standards to be met. Many owners and designers from the Western world will also choose to use American or British standards in addition to or in lieu of local code. This takes reaching agreement with the local authorities. If American codes are used, either the International Building Code (IBC) or NFPA 5000: Building Construction and Safety Code are used as the building code, with other NFPA standards used for fire protection systems.
Heffelmire: For this project we used the Florida Mechanical and Plumbing Code in affect at the time and NFPA where applicable.
CSE: Have Energy Star, ASHRAE, U.S. Green Building Council, etc., affected your work on tall/super-high-rise projects? What are some positive/negative aspects of these guides?
Heffelmire: Energy Star, ASHRAE, USGBC, and other groups have all equally influenced the design decisions on all our buildings, including the high-rises. As a firm, as of this date, we have completed more than 242 LEED-certified projects, many of which were LEED Platinum.
CSE: Which code/standard proves to be most challenging in such facilities?
Quiter: The biggest challenge with codes and standards is trying to meet both local and foreign standards. Many codes take different and, at times, conflicting approaches, so strict adherence may not be possible. The design team needs to make informed decisions, document them, and reach agreement with the authorities before proceeding with design.
Jalayerian: Most building codes are written for good design and construction practices applicable to typical buildings. The most challenging issues among super-tall or high-rise buildings are consequences of a lack of coordination of one requirement of code with respect to performance of another requirement of the code or standard. For example, integrating a locality’s preference for operable windows while mitigating the stack effect performance of super-high-rise buildings is a significant challenge and imposes considerable installation and operational cost on the building.
Heffelmire: The USGBC requirements for LEED Certification are the most challenging for our projects and the most gratifying.
CSE: Do you find codes affecting tall/super-high-rise structures to be more or less taxing than those impacting work on other building types?
Heffelmire: Codes that affect super-high-rise structures are more taxing than other building types, especially when it comes to life safety, security, fire, and communication systems. ASME A17.1, Safety Code for Elevators and Escalators is very important and when elevator engineers are able to make elevators travel even higher, we will see taller buildings. The sky’s the limit.
Quiter: The challenge with tall buildings is that the codes were not written around such unusual buildings. While some code provisions are being written around very tall buildings, they cannot address (nor should they) all the decisions that must be made. That is why the International Code Council (ICC) and Society of Fire Protection Engineers (SFPE) developed the Guidelines for Designing Fire Life Safety in Very Tall Buildings. (I chaired the committee.) The guide is written to provide information from which the designer and owner can make informed decisions. It is intentionally written to not be adopted as an enforceable code. Unique buildings require unique solutions, not code solutions. Therefore, designing very tall buildings is more taxing, not due to the codes, but due to the thinking, decision-making, and teamwork that must occur.