On Monday, 24 June 2024 the CTBUH Height & Data Committee met for the first time since 2022, reinvigorating and relaunching this prestigious CTBUH committee under the leadership of the new Chair, Terri Meyer Boake, a CTBUH Fellow and Full Professor at the School of Architecture at the University of Waterloo in Canada, who joined the CTBUH staff in Chicago for this milestone.

A diverse range of disciplines and regions were represented, with 24 CTBUH experts from architecture, structural engineering, construction, and academia joining the meeting from Asia, Europe, the Middle East, North and Latin America, and Oceania. First, the committee reviewed existing Tall Building Criteria, which has already been created, agreed, and established by this committee. Some prior highlights were also shared with the attendees, including the affirmation of One World Trade Center's height, which allowed the building to be designated the Tallest Building in North America and garnered significant media attention.

Next, each committee member introduced themselves, and shared their background and interest in this committee. Following the introductions, the committee discussed some of the topics that will be discussed and deliberated in future meetings. Some of these topics include:

• What is the difference between Composite and Hybrid structures?

• Should prefabricated or modular buildings be distinguished from in situ construction?

• How much of a certain material must be in a buildings structure, to be considered Composite and/or Hybrid, as opposed to an All-Steel or an All-Concrete building, for example?

• How is the occupiable space measured in building's with excessively large floor-to-ceiling heights or atriums?

• How are staged completions vs. renovations distinguished?

Then, the rejuvenated Committee considered and voted on their first decision; based on a petition from a CTBUH member, it was requested that the CTBUH Height & Data Committee define the term "twin," in order to bestow titles such as "Tallest Twin Buildings in the World." This petition passed, and the Committee decided to discuss and examine two-building-complexes further, and determine which examples qualify as "twin buildings."

At the close of the meeting, members discussed next steps, future meetings, and attendees were asked to read and consider a paper, which was recently published based on collaborative research and writings created by three members of this committee: Embodied carbon premium for vanity height: A case for the exclusion of decorative spires in the design of tall buildings, by James Helal (University of Melbourne), Dalibor Savovic (DeSimone Consulting Engineers), and Dario Trabucco (CTBUH & Università Iuav di Venezia).

Stay tuned as the committee and CTBUH digest all that was discussed and begin to release more details.