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Stepping Outside the Lines but Staying Within the Framework

The Delicate Dance of Code Innovations (Part 2)

Alan Scott And Samir Mokashi

Last month, we looked at innovative approaches to code compliance with fire protection of steel, in both renovation and new construction projects while supporting building function, material efficiency and air quality. In this second of a three-part series, we will explore creative code analysis and application to address life safety and exiting requirements in existing buildings, bringing new life to existing buildings. According to Architecture 2030, the embodied carbon in building products is responsible for 11 percent of total global greenhouse gas emissions and 28 percent of global building sector emissions. Further, it is estimated that embodied carbon in building materials will represent almost half of all new construction emissions between now and 2050.

Clearly, preserving the embodied carbon in existing buildings is a key part of reducing the overall emissions from buildings as we address the building sectors significant climate impact. However, the adaptive reuse of existing buildings can present conflicts between modern programmatic needs, the practicalities of cost-effective construction, and code limitations. To illustrate, let’s look at two project examples of code solutions that helped make new uses work in existing buildings.

The first project is the adaptive reuse of two adjacent historic buildings in downtown Portland, Ore. The project combined the Woodlark Building, built in 1912, with the Cornelius Hotel, built in 1908, to create a new 150-room lifestyle hotel. These structures had a lot of building and fire code challenges to solve before the developer’s vision could be realized. For starters, the Cornelius was wood construction while the Woodlark was concrete construction. The Oregon building code does not permit buildings of differing construction types to be combined as a single building. The code permits the renovation of an existing building without upgrading it to meet all provisions mandated for new construction. However, when two different structures like these are combined, the code applies as if it were a new building and requires that it satisfy all requirements applicable to new construction. This degree of upgrade would have pushed the project beyond economic feasibility.

Code Unlimited worked closely with the City of Portland to negotiate and win approval for 10 appeals, allowing the project to proceed. The biggest early breakthrough was getting the city to accept that the two buildings could be considered a single building of type IB construction. The city agreed on the condition that the Cornelius be upgraded to meet type IIIA construction and that no future additions to the structure would be permitted. Another challenge was that each building had only one enclosed stair. The combined building had two enclosed stairs, but the Cornelius was only seven stories while the Woodlark was nine stories tall. The design team proposed adding a stair that extended above the roof of the Cornelius building to provide the second exit from the eighth and ninth floors and then connected to the existing stair by a one-hour rated corridor. A creative approach to code compliance allowed this successful project to give new life to two century-old buildings.

Cornelius Woodlark Building, courtesy of Michael Gregg_Atomic Sky

The second project involved a multi-floor tenant in a Seattle high-rise wanting to implement a simple interior remodel to meet changing needs without necessitating to move. The design for the four-floor office renovation included a spacious employee lounge on the 36th floor, and an internal communicating stair between the 35th and 36th floors. Unfortunately, that lounge increased the calculated occupant load to over 500 persons on this floor. The building has only two exit stairs, and the current Seattle Building Code required a third exit based on the new occupant load. It was obviously infeasible to add a new stair extending from the 36th floor all the way to the ground floor. Since the building was of Type IA construction (the most protected construction type), a horizontal exit would have been a practical and code compliant solution in most jurisdictions. However, when it was adopted, the 2015 Seattle Building Code amended section 1006.3 of the 2015 IBC to include language that prohibits horizontal exits as one of the required number of exits.

Code Unlimited was engaged to find a solution. After extensive deliberation, presenting evidence that horizontal exits work and save lives, the city reviewers were still unwilling to change their position. Code Unlimited proposed a performance analysis of the 36th floor using a specialized software called Pathfinder to simulate egress conditions and demonstrate the validity of a solution. The software creates a 3-D animation of occupants egressing from different locations on the floor to the exits. The simulation compared two conditions, one with two enclosed exit stairs, one horizontal exit, and the internal communicating stair, and the other with three enclosed exit stairs. The timed-egress analysis revealed that emergency evacuation using the horizontal exit option took less time than three enclosed exit stairs required by current code. The compelling results were presented to the city reviewers, using state-of-the-art fire science and video evidence from the simulation, and it convinced them to change their minds. Now they are reviewing their stance on horizontal exits opening the door for other projects to benefit from this approach.

Codes are intended to protect health and life safety, including bringing existing buildings into compliance when renovations are proposed. However, codes can also be inflexible when it comes to the unique circumstances presented by upgrades and changes of use in these buildings. Fortunately, good old fashioned creative problem solving, combined with state-of-the-art simulation tools, can illuminate solutions that meet code intent, and also preserve historic resources, embodied carbon and project proformas. Next month, we will review some additional examples of creative code applications.


Alan Scott, FAIA, LEED Fellow, LEED AP BD+C, O+M, WELL AP, CEM, is an architect with over 30 years of experience in sustainable building design. He is a senior associate with WSP in Portland, Ore. Samir Mokashi, is the founder and principal of Code Unlimited in Beaverton, Ore. He has more than 25 years of architectural and code consulting experience, codeul@codeul.com. To learn more, visit www.wsp.com/en-US/services/built-ecology and follow Scott on Twitter @alanscott_faia.