About the Council The Council on Tall Buildings and Urban Habitat (CTBUH) is the world’s leading resource for professionals focused on the inception, design, CTBUH Journal construction, and operation of tall buildings and International Journal on Tall Buildings and Urban Habitat future cities. Founded in 1969 and headquartered at Chicago’s historic Monroe Building, the CTBUH is a not-for-profi t organization with an Asia Headquaters offi ce at Tongji University, Shanghai, a Research Offi ce at Iuav University, Venice, Italy, and an Tall buildings: design, construction, and operation | 2017 Issue IV Academic Offi ce at the Illinois Institute of Technology, Chicago. CTBUH facilitates the exchange of the latest knowledge available on tall buildings Special 2017 Conference Themed Issue: Australia around the world through publications, research, events, working groups, web resources, and its Shaping Sydney’s Public Realm through Design Competitions extensive network of international representatives. The Council’s research department is spearheading Rethinking CTBUH Height Criteria for Tall Timber the investigation of the next generation of tall buildings by aiding original research on sustainability How to Balance Sydney’s Airport and Urban Expansion Goals? and key development issues. The Council’s free database on tall buildings, The Skyscraper Center, is Debating Tall: Is Australian High-Rise Housing on the Right Track? updated daily with detailed information, images, data, and news. The CTBUH also developed the In Numbers: Rising Up Down Under international standards for measuring tall building height and is recognized as the arbiter for bestowing such designations as “The World’s Tallest Building.” CTBUH Headquarters 104 South Michigan Avenue, Suite 620 Chicago, IL 60603, USA Phone: +1 (312) 283-5599 Email: [email protected] www.ctbuh.org www.skyscrapercenter.com CTBUH Asia Headquarters College of Architecture and Urban Planning (CAUP) Tongji University 1239 Si Ping Road, Yangpu District Shanghai 200092, China Phone: +86 21 65982972 Email: [email protected] CTBUH Research O ce Iuav University of Venice Dorsoduro 2006 30123 Venice, Italy Phone: +39 041 257 1276 Email: [email protected] CTBUH Academic O ce S. R. Crown Hall Illinois Institute of Technology 3360 South State Street Chicago, IL 60616 Phone: +1 (312) 567 3487 Special Issue Email: [email protected] Sponsored by: ISSN: 1946 - 1186 Inside News and Events Features 28 CTBUH Special Report Rethinking CTBUH Height Criteria new challenges. Among these is the need to to be “tall,” in the sense of “tall for a timber or update the language that is used to describe unreinforced-masonry building.” Tallness in In the Context of Tall Timber tall buildings; to move beyond descriptors this sense is important to the design suited solely to a palette of materials limited community, because the practice of design Abstract by the historical duopoly of steel and must draw on both experience and 02 This Issue 48 Tall Buildings in Numbers Recent developments in the design and construction of progressively taller concrete. A proposal addressing this challenge theoretical understanding. Buildings that buildings using engineered timber as a structural material raise important was presented previously by the authors for exceed the height of precedents using questions about the language that is used to describe tall buildings. This paper discussion within the structural engineering similar materials or systems thus present community (Foster et al. 2016). This version of additional challenges to designers. discusses the role of the CTBUH Height Criteria in classifying tall buildings and the the paper provides a summary of the Daniel Safarik, Going Up Down Under: challenges raised by the emergence of engineered timber as a contemporary supporting discussion to the wider tall Another contextual consideration that has Robert M. Foster structural material alongside steel and concrete. The paper concludes by building community. historically played a role in the technical definition of a building’s tallness is that of fire. presenting a proposal for updating the existing terminology to accommodate the Figure 3. River Beech Tower, Chicago. © Perkins + Will use of timber and other new materials in the design of tall buildings. This paper will The generally accepted terminology for the A building has often been considered “tall” in be used as a basis for discussion at the CTBUH Workshop on Tall Timber, held in classification of tall buildings is set out by the this sense if its height is such that a fire Proportion can be thought of as considering a Editor Australia’s Burgeoning CTBUH Height Criteria and this has been cannot be fought using ground-based building in the context of its own geometry conjunction with the 2017 Conference, with a view towards the future revision of shown to be highly appropriate for the tall equipment. This has constituted an historical and massing. A 14-story building on a small the CTBUH Criteria to include timber. buildings of the last century. However, in “basic height limit” in North America and footprint might be slender and thus appear order to encourage productive discussion and elsewhere (Calder et al. 2014). tall, in a way that a 14-story building covering Keywords: Height Definitions, Building Criteria, Timber, Materials Dr. Michael H. Ramage Dr. Thomas Reynolds ensure that meaningful comparisons can be an entire city block might not. An indicative Skylines Introduction heights up to 80 stories, including the River made between a wider range of emerging The CTBUH identifies three further qualities characterization of tallness with respect to Authors Beech Tower, Chicago and Oakwood Tower, building systems and materials, it is useful to that can be used to define tallness: height height relative to context and slenderness is Robert M. Foster, Senior Lecturer Between 1885 and 1913, the development of London (see Figures 3 and 4) (Green & Karsh revisit and perhaps clarify these criteria. The relative to context, proportion, and use of tall shown in Figure 5. School of Civil Engineering steel-framed structural systems permitted the 2012, SOM 2013, Foster & Ramage 2016). basis for this clarification is both the historic building technologies. University of Queensland 49 Advanced Engineering Building heights of skyscrapers to leap from the Although it is impossible to know what and commonly understood thinking behind Tall building technologies are features such as Staff House Road 10-story Home Insurance Building in Chicago, heights tall buildings using engineered timber the existing terminology and definitions, and Height relative to context acknowledges that a advanced vertical transportation and 04 CTBUH Latest St Lucia QLD 4072, Australia t: +61 7 3365 3619 to the 60-story Woolworth Building in New might ultimately reach, the historical also an understanding of the future directions building’s surroundings play an important enhanced lateral force-resisting and damping e: [email protected] York. Only 18 years later, the Empire State precedent and the potential identified in of tall building construction. part in assessments of tallness. A 14-story systems that are particular to the design of tall http://www.civil.uq.edu.au Building was completed at a height of 102 recent design proposals suggest that residential building sited in a suburban buildings. Enhanced lateral force-resisting and Dr. Michael H. Ramage, Director stories. Between 2008 and 2016, the height of genuinely tall timber buildings are likely to neighborhood might be described as tall, damping systems are closely related to the Centre for Natural Material Innovation Antony Wood, 50 Talking Tall: Kim H. Nielsen Department of Architecture, University of Cambridge modern buildings using engineered timber become a reality in the very near future. Tallness while the same building situated in a slenderness of a building. This aligns with the 1 Scroope Terrace increased from the nine-story Stadthaus high-rise cityscape might not be. structural engineer’s definition of “high-rise Cambridge CB2 1PX, United Kingdom t: +44 1223 760 121 building in London to the 17-story TallWood The opportunities for better, more sustainable Definitions of “tallness” are subjective and e: [email protected] at Brock Commons building in Vancouver (see tall buildings afforded by new materials, new dependent on context. In historical terms, a www.natmat.group.cam.ac.uk Figures 1 and 2) (CTBUH 2017). Designs have construction technologies and new building that is taller than previous buildings Executive Director Humanizing the High-Rise Dr. Thomas Reynolds, Chancellor’s Fellow also been presented for timber skyscrapers at architectural forms bring with them a range of of a particular material or type might be said Institute for Infrastructure & Environment The University of Edinburgh 1.22 William Rankine Building, The King’s Buildings Edinburgh EH9 3JL, United Kingdom t: +44131 650 5633 e: [email protected] www.eng.ed.ac.uk/research/institutes/iieof 05 Debating Tall: 54 Ask a CTBUH Expert: Robert Foster will present this paper and provide an update on the results of the “Pre-Conference Workshop on Tall Timber” in Is Australian High-Rise Amin Hamzavian Session 3C: Tall Timber, Monday 30 October at 1:45 p.m. Figure 1. Stadhaus, London. © Will Pryce Figure 2. TallWood at Brock Commons, Vancouver. Housing on the Right Track? How to Balance Sydney’s © Acton Ostry Architects & University of British Columbia Figure 4. Oakwood Tower, London. © PLP Architecture Figure 5. Appearance of tallness. 28 | CTBUH Special Report CTBUH Journal | 2017 Issue IV CTBUH Journal | 2017 Issue IV CTBUH Special Report | 29 Objectives for Airport and 06 Global News Urban Expansion? Highlights from the CTBUH Global News archive 40 Urban Design Empirically Evaluating the Livability Solutions for Spatial Planning (SSSP) (Derix Dynamics are expressions of the urban have started to provide curated databases, 2012), and began to complement their systems that define cities, and hence, the city such as NYC Open Data or the London Of Local Neighborhoods and Global Cities computational urban design and planning has to be understood as a much larger Datastore.