Historic structures may seem to be an unlikely setting for contemporary advances in fire protection, but some of the most historic buildings in Greater New York City have inspired advances that continue to have application worldwide. I was thinking about that as I prepared a recent presentation for a virtual conference in Europe.
‘Historic’ means something different in New York City than it means in Europe, of course. Construction began in 1930 on the Empire State Building, where I have designed and managed significant engineering upgrades, including retroactive sprinkler installations. By contrast, construction began on the Cathedral of Notre-Dame in Paris in AD 1163 – and on the Pantheon in Rome in AD 113.
Still, historic structures have in common a need to meet contemporary safety expectations within the context of not only historic preservation but a deference to the spirit and the purpose of the original structure. That’s what makes addressing the fire protection needs of historic structures so fascinating. It’s why addressing those needs is essential to historic preservation itself. It’s how historic structures fuel the creativity today that leads to innovation.
A secular analogy to the soaring interiors of Europe’s great cathedrals can be found in the Main Concourse of New York City’s Grand Central Terminal, an unrivalled civic sanctuary. There, our consulting engineering firm Goldman Copeland had the challenge of designing life safety systems while preserving the awe-inspiring interior with its stunning celestial ceiling. That interior welcomes hundreds of millions of visitors in a normal year, making the Terminal one of the world’s most visited locations.
We installed sprinkler systems throughout the building, except in the Main Concourse. A sprinkler system in the Main Concourse would not only have compromised the aesthetics of the ceiling, but, because of the ceiling’s height, water would be an ineffective mist before it reached the occupant level. Instead, we focused on automatic smoke removal – to protect occupants, first and foremost – and creatively integrated infrastructure improvements with the historic fabric of the building.
We used the original decorative ceiling grilles, called roundels, at Grand Central Terminal for an emergency smoke control system, whose performance we verified by fire modelling. Careful coordination with historic building experts – in this case, the architecture firm of Beyer Blinder Belle – produced a design and execution that does not distract in any way from the stunning setting and has been honoured by the New York Landmarks Conservancy.
We continue to apply that approach to historic houses of worship, where we typically recommend placing a sprinkler system in the attic – sometimes a dry pipe sprinkler system. We typically do not install sprinklers in main sanctuaries, where the aesthetics would be adversely affected. We employ other strategies to save lives in sanctuaries such as early detection, automatic smoke control exhaust systems, and more passive solutions such as fire-rated separations and fireproofing of structural elements.
A different challenge involving a sanctuary required a computer-modelled response at Audible’s new headquarters – known as the ‘Innovation Cathedral’ – in downtown Newark, New Jersey. There we helped convert an abandoned historic (1932) church into a cutting-edge corporate facility – and a centrepiece for the flourishing tech community. The repurposed 80,000ft2 church, with its landmarked exterior, includes dual atriums – the 55ft-high former nave and the 35ft-high adjacent community hall.
The two side-by-side atriums presented an unusual challenge, as any smoke being emitted or removed from one atrium could fill the other. To address the challenge, we built a computer-based model that projected the paths of any potential smoke. We then designed ways to remove any smoke and maintain a clear safe path of egress. The resulting fire-modelling system pressurized one atrium while exhausting the other.
At the ‘Innovation Cathedral’, the challenge was to manage any smoke that might arise. At One Grand Central Place, an historic office building directly across 42nd Street from Grand Central Terminal, a different fire-modelling challenge arose: determining how long it would take for a sprinkler to activate.
There, we needed to sprinkler an historic lobby with an ornate, vaulted, plaster ceiling – without damaging the ceiling. One solution that we ultimately dismissed was to delicately remove portions of the ceiling before installing the sprinklers and re-installing the ceiling. That proved not only to be prohibitively expensive but potentially destructive. Plaster is notoriously fragile, and even the effort to remove it carefully might damage it irreparably.
Computer-based fire modelling provided an alternative that subsequently proved successful. Instead of placing the sprinklers in the ceiling, we could place them high on the side walls supporting the ceiling, if we could prove that the wall-mounted sprinklers would activate as quickly as ceiling-mounted ones. The fire modelling demonstrated that equivalent protection would be achieved. The City of New York’s Department of Buildings reviewed our calculations and approved the alternative approach.
This approach had another practical benefit for the owner and occupants of the building. Where installing ceiling-mounted sprinklers would have required closing much of the lobby for extended periods of time, most of the preparatory work for installing the wall-mounted sprinklers could be conducted in adjacent space. As a result, the installation never required closing the lobby.
Historic properties are especially well suited to performance-based designs. That’s because aesthetic concerns often cannot be addressed creatively through standard prescriptive codes, which may not anticipate, for instance, how ornate or historic a particular ceiling may be.
Performance-based design starts with a thorough understanding of the unique setting and requirements. Fire protection goals are defined at the outset, almost always including protecting life safety and property. Other goals may include mission continuity as well as addressing specific circumstances such as preserving historic features.
Once the fundamental goals are established, more specific criteria are developed to address additional stakeholder priorities. The emerging design may then incorporate through fire modelling such tactics as passive system considerations, fire alarms, life safety and property protection, beam detection and wireless systems, smoke control, ventilation and flushing, fire suppression and control, sprinkler and water mist systems, and clean agents.
At the historic Empire State Building, perhaps the best-known office building in the world, the lobby has been designated a national historic landmark and is, therefore, exempt from needing sprinklers. But that was not true for the rest of the building, where retroactive sprinkler installations were required by Local Law 26 of 2004 for office buildings 100ft or more in height. The Empire State Building is more than 100 stories in height – 102 in all.
I oversaw the entire effort for the owner – Empire State Realty Trust – the legally mandated deadline for which was 1 July 2019. The effort was massive, given the height of the building. It involved not only tenant improvements on the many floors of office space but also the installation of sprinklers in the public spaces, including the famous viewing platforms and the restaurants and shops. It also required specialty fire protection equipment for the floors near the top of the building that house broadcasting equipment for television and radio stations.
The entire retroactive installation was completed well in advance of this year’s 90th anniversary celebration of the Empire State Building. It opened on 1 May 1931, after a record-breaking one year and 45 days of construction.
‘Historic’ does not mean ‘set in the past’. Rather, it inspires innovation, because there are unique qualities that must be preserved while addressing contemporary expectations. The soul of an historic building must be maintained, even as the building’s life safety systems are updated to ensure contemporary protection, relevance, enjoyment – and inspiration.
New computer-based tools make that challenge more creative than ever. The solutions can then be applied to historic and more recent structures worldwide, ensuring that our respect for the past is maintained as our vision for the future grows even clearer.
For more information, go to www.goldmancopeland.com