Changing the code
By David Vanderhoff
June 8, 2015
Each article in our Design Details series focuses on a single innovation from a design project. For our first post: the Philadelphia fire stair that wasn’t.
Although their work is typically visible only in a sprinkler here or a protective coating there, fire engineers work closely with the full architectural team at every stage of a complex building project. Aesthetic considerations, sustainability goals, construction costs, and shifting code requirements all influence a building’s fire safety design, necessitating a truly comprehensive perspective.
“When we provide fire consulting services, we look at the building as a whole,” Ray Grill, head of Arup’s fire engineering group in the Americas, told me. “First and foremost, we want to have a safe building. Then we look at ways to make it more efficient.”
A new Philadelphia landmark
Case in point: a project currently rising in Philadelphia’s University City neighborhood. The tower will soon reach a height of 750 feet, making it the one of the largest mixed-use developments outside the downtown core. Named after a chemical company whose headquarters it will house, the 49-story FMC Tower will also contain facilities for the University of Pennsylvania, more than 250 residential units, and ground-floor restaurant and retail spaces.
As plans for the building began to take shape, Grill and his team set to work assessing potential issues. “The key is developing solutions early in the design process,” he said. They were responsible, in particular, for ensuring that the design would meet the building code’s fire safety requirements.
The team soon concluded, however, that the applicable code requirements were unnecessarily cumbersome. Because of its height and the fact that its upper stories house short-term residential units, the building was subject to a recent code modification requiring a redundant fire stair.
This requirement was problematic for several reasons. It would increase construction costs and compromise the efficiency of the floorplate design. Moreover, according to Grill, the additional stair was completely unnecessary, adding nothing to the safety of the building.
Building codes are constantly in flux, updated every three years. Modifications are sometimes introduced in response to disasters, technological shifts, and political pressures. But however well-intentioned, these changes don’t always result in the most effective building standards.
In the case of the extra fire stair, Grill saw no rationale beyond a political and emotional gesture. “That requirement, in my opinion, was a knee-jerk reaction to 9/11. If you need a stair, you need a stair. There’s no reason for redundancy.”
Building codes are constantly in flux.
The team considered alternatives (e.g., evacuation elevators) to satisfy the code requirements, but ultimately rejected them as costly and inefficient. In the end, they decided to challenge the code itself, applying to the Philadelphia Board of Building Standards for a variance.
Their argument hinged on demonstrating that the additional stair was unnecessary and that the building’s safety provisions already satisfied the intent of the code. The variance was approved, and the project moved forward with a more efficient and cost-effective design.
Grill used the insights gained from this project to push for intelligent changes to the building code. This year, the International Code Council is considering his proposal to eliminate the redundant stair requirement for certain building types — along with ten other changes he has proposed in this cycle.
“I think that engineers involved in building design and construction are in the best position to propose code modifications that make sense,” he said. “Oftentimes, a person submitting a proposed code change is only considering a single instance, and not the breadth of potential applications of that code.”
“New code requirements often have unintended consequences. When you propose code modifications, you have to be thoughtful.”
This is post 1 of 2 in the Design Details series
- The multimedia museum / Jul 9, 2015
- Changing the code / Jun 8, 2015