Lessons from 9/11: High-Rise Intl. Building Code Changes

Nov. 6, 2008
In September 2008 – 7 years after the collapse of the World Trade Center – the Intl. Code Council (ICC) approved 23 wide-ranging building and fire code changes that will impact the way tall structures are planned, designed, and built

The Intl. Code Council approved 23 wide-ranging building and fire code changes that will impact the way tall structures are planned, designed, and built in the United States. Whether this significant change will lead to innovation in the built environment, as well as in the global political landscape, remains to be seen.

By Barbara A. Nadel, FAIA

The United States has elected a new president – one who represents a new direction in American history. As the world witnesses the process leading to an orderly transition of power on Jan. 20, 2009, we are reminded that change takes time in politics – and in design and construction, and in the often arcane world of building codes.

In September 2008 – 7 years after the collapse of the World Trade Center – the Intl. Code Council (ICC) approved 23 wide-ranging building and fire code changes that will impact the way tall structures are planned, designed, and built. The code changes reflect the recommendations from the National Institute of Standards and Technology (NIST) investigation of the collapses of New York City’s World Trade Center (WTC) towers on 9/11, which resulted in the deaths of about 3,000 people.

The changes will be incorporated into the 2009 edition of the ICC’s I-Codes (the Intl. Building Code, or IBC, and the Intl. Fire Code, or IFC), a model code used as the basis for building and fire regulations promulgated and enforced by U.S. state and local jurisdictions, which have the option of incorporating some or all of the code’s provisions, but typically adopt most of them. The proposals were developed and refined based on feedback from many U.S. building and fire code experts.

The new provisions address many areas relating to design, construction, and emergency egress from tall buildings, such as increasing structural resilience to building collapse from fire and incidents, requiring a third stairway for tall buildings, increasing width of all stairways by 50 percent in new high-rises, calling for luminous markings delineating exit paths in buildings more than 75-feet tall to facilitate rapid egress and full building evacuation, and a host of other recommendations relating to construction and emergency response.

Nine code change proposals based on the NIST WTC recommendations were not approved for the 2009 edition of the I-Codes, but will most likely be revisited for adoption in the future. Two in particular have significant impact on building security: designing structures to mitigate disproportionate progressive collapse, and requiring risk assessments for buildings with substantial hazard, which includes buildings taller than 420 feet with more than 5,000 occupants.

Impact of Change
According to the Council on Tall Buildings and Urban Habitat, developers and major cities around the world are building super-tall structures. In Dubai, the world’s tallest tower is under construction. The Nakheel Harbour & Tower, taller than 3,281 feet (1,000 meters), with more than 200 floors that can be occupied, is projected for completion in 2020. This project supplants the record currently held by the Burj Dubai, in the same booming city, at 2,600-plus-feet tall (800-plus meters), with more than 160 floors that can be occupied.

Tall building conferences in Dubai, Moscow, and the Republic of Kazakhstan in 2008 attest to the widespread belief among global developers that the demand for occupiable space in growing urban centers, coupled with willing investors and significant profit margins, make these buildings viable projects in developing regions and established markets alike.

The impact of the fall 2008 financial collapse in the United States remains to be seen on global megaprojects and other design and construction work planned in the United States and elsewhere. The sources of investment capital, especially if government backed or privately financed, will likely play a key role in determining which projects go forward. In the United States, reports of construction loan delinquencies have risen to an estimated 10 percent in the third quarter of 2008, resulting in an increasing number of commercial construction projects that are slapped with liens or end up in litigation.

Around the world, rising costs of labor, energy, transportation, and building materials strain budgets and fees that were developed in the past few years, and exceed projected inflation rates. In nations where construction practices and code enforcement are lax, it’s possible that building materials, construction methods, and safety features deemed essential in the United States may be replaced, reduced, or eliminated as cost-saving measures. The public may never know which corners were cut to save money until a tragedy occurs.

The continued demand for tall buildings, along with the potential for terrorist threats and catastrophic events, remain primary concerns in many parts of the world. With thousands of building occupants confined to a vertical sliver of construction, concerns for public safety, full evacuation, egress systems, fire protection, and overall building security cannot be underestimated or overlooked.

As the ICC changes illustrate, the issue of total building evacuation, instead of only providing areas of refuge on designated floors, acknowledge the post-9/11 realities of incidents that might cause buildings to collapse and burn, and the need to evacuate thousands of people within a short timeframe. The ease of delivering a powerful vehicle-borne improvised explosive device (IED) or a suicide backpack bomb is too big of a risk to ignore during the early planning and design phases.

Globally, building codes from the United States, the U.K., and Australia are widely recognized in countries that lack their own comprehensive, modern building codes that protect public health, safety, and welfare. Time will tell whether the NIST-driven ICC changes will make their way into other widely used building codes, or be adopted in countries that use the IBC as their model code.

According to Clark Manus, CEO and CFO at Heller-Manus Architects in San Francisco, “The ICC code change that relates to the requirement for a third stair for buildings over 420 feet in office buildings may precipitate a significant rethinking of increased height and the associated urban design and planning principles pertaining to the viability of slim towers in the urban cores of major cities. While the code change would permit special provisions to be incorporated in elevators with special features in lieu of a third stair, design concepts will likely change as architects and engineers understand the balance in creating efficient buildings. Safety is a major aspect of this ICC change; the increased use of technology in vertical transportation may be worth exploring in future code changes.”

Change Can Lead to Innovation
Meanwhile, the new code changes can inspire manufacturers and building industry groups to develop new materials and technology that respond to safety, security, and sustainability – the three most important concerns in a changing global economy. Sandia National Laboratories in New Mexico is partnering with an established manufacturer to develop wall systems that provide blast resistance and fire protection while being lightweight, sustainable, and made in the United States. Furthermore, communications systems for radios and emergency response are integral to the ICC code changes, and they may provide new opportunities for development of systems and equipment.

Understanding building codes and standards, and the role they play in planning and design of commercial buildings – not just high-rises – should be taught in schools of architecture and engineering, as well as continuing-education programs. The design professionals of tomorrow need to understand the impact of change on today’s built environment, as well as on the global political landscape.

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