About the Council

The Council on Tall Buildings and Urban Habitat, based at Institute of CTBUH Journal Technology in Chicago, is an international International Journal on Tall Buildings and Urban Habitat not-for-profi t organization supported by , engineering, planning, development, and construction professionals. Founded in 1969, the Council’s mission is to disseminate multi-disciplinary information on Tall buildings: design, construction, and operation | 2013 Issue III tall buildings and sustainable urban environments, to maximize the international interaction of professionals involved in creating the built environment, and to make the latest Case Study: The Bow, Calgary knowledge available to professionals in a useful form. Debating Tall: Do Trees Belong on ?

The CTBUH disseminates its fi ndings, and Imagining the Tall Building of the Future facilitates business exchange, through: the publication of books, monographs, The Use of Stainless Steel in Second-Skin Façades proceedings, and reports; the organization of world congresses, international, regional, and Politics, History, and Height in Warsaw specialty conferences and workshops; the maintaining of an extensive website and tall Using CFD to Optimize Tall Buildings building databases of built, under construction, and proposed buildings; the distribution of a Tall Building in Numbers: Vanity Height monthly international tall building e-newsletter; the maintaining of an Talking Tall: Tall Timber Building international resource center; the bestowing of annual awards for design and construction Special Report: CTBUH 2013 Conference excellence and individual lifetime achievement; the management of special task forces/ working groups; the hosting of technical forums; and the publication of the CTBUH Journal, a professional journal containing refereed papers written by researchers, scholars, and practicing professionals.

The Council is the arbiter of the criteria upon which tall building height is measured, and thus the title of “The World’s Tallest Building” determined. CTBUH is the world’s leading body dedicated to the fi eld of tall buildings and urban habitat and the recognized international source for information in these fi elds.

Council on Tall Buildings and Urban Habitat

S.R. Crown Hall Illinois Institute of Technology 3360 South State Street Chicago, IL 60616 Phone: +1 (312) 567 3487 Fax: +1 (312) 567 3820 Email: [email protected] http://www.ctbuh.org

ISSN: 1946 - 1186 Inside

News and Events Features 20 Sustainability/Green/Energy Can You Imagine the Tall Building of the Future? Predicting the future is an impossible task. One will never get it absolutely In the high-rise of 2050, materials will right. However, that does not make it a pointless exercise. Instead, such a discussion is a tool to enable conversations about the possible, and to inspire “feature intelligent design and will be formulated 02 This Issue 44 Tall Buildings in Numbers people to think beyond today and look at some of the trends that will shape as high-performance composites made from our future. recycled and renewable elements, providing Josef Hargrave Ralph Wilson The below text and corresponding illustration “internet of things.” These expectations set the functions such as self-repair or purification of (see Figure 1) do not aim to depict what all tone for an environment that invites Cathy Yang, Vanity Height: The Empty Authors buildings, or even all tall buildings, will look adaptation with ease; a place where hard Josef Hargrave, Senior Consultant, Foresight + the surrounding air. Innovation like in the future. Instead, we want to create a infrastructure, communication and social Ralph Wilson, Mechanical Engineer Arup vehicle for conversation. We present a tool to systems are seamlessly intertwined with a ”

13 Fitzroy Street highlight some of the functions and conscious necessity to integrate and engage functioning as a living organism in its own physical limits, and to shape a new type of London W1T 4BQ characteristics we may expect from cities and in sustainable design practices. right – reacting to the local environment and urban experience. CTBUH Trustee Space in Today’s Tallest United Kingdom buildings in the future, and to explore what engaging the users within. A dynamic t: +44 20 7755 4357 e: [email protected] / [email protected] that may entail and for the sector as a whole. network of feedback loops, characterized by www.driversofchange.com / www.arup.com smart materials, sensors, data exchange, and Can You Imagine a Building that Has a Figure 2. Flight Assembled Tower. © Francois Lauginie automated systems merge together, virtually Flexible Components Designed for Josef Hargrave Can You Imagine? functioning as a synthetic and highly sensitive Continuous Adaptability? Josef Hargrave is a senior Foresight and Innovation consultant at Arup. He is responsible for the firm’s Future technology will be far more focused on nervous system. In this sense, the building’s foresight activities and consulting services across By 2050, the human population will have producing unique solutions for individual structure is highly adaptive and characterized In this emerging age, significant develop- the Europe Region. Josef works for clients spanning a wide variety of sectors and markets. His projects reached nine billion; of this, 75% will be living people. The necessity for our surrounding by indeterminate functions – a scheme in ments in construction will advance current combine corporate foresight with Arup’s global in cities. Until then, climate change, resource environment to inherently understand an which space and form are manipulated practices – prefabricated and modular engineering and consulting expertise, providing scarcities, rising energy costs and a individual’s preferences and personal needs depending on the time of day or the user structural systems will be moved and 04 CTBUH Latest 46 Talking Tall: Finding the clients with unique insights on the future of the built environment. Josef’s passion is the future of cities: the preoccupation with preventing and means all facets of the building network could group currently activating the structure. The assembled by robots that work seamlessly structures, spaces, technologies and experiences that will make life in the city sustainable in the long-term. minimizing the effects of the next natural or respond to the specifics of each unique user, system presents a spatial and formal condition together to install, detect, repair, and upgrade man-made disaster will undoubtedly shape down to an individual’s genetic composition. that changes constantly. The structure’s components of the building system. Ralph Wilson our vision of the built environment. As major components are designed to be dynamic, Technology, spaces and facades will be rapidly Antony Wood, Forest Through the Trees – Ralph Wilson is a mechanical engineer and cities reach their boundary limits, extending In 2050, the urban dweller and the city are in a intelligent and reactive – it is a living structure modifiable, dictated by factors such as the sustainability specialist based in Arup’s Building Engineering London group. He is an innovation transit networks and patterns of urban sprawl state of constant flux – changing and evolving activated by interaction with the users and its addition or subtraction of program, density of enthusiast with a curiosity for the novel, and a particular interest in design that supports will no longer provide an effective solution. in reaction to emerging contexts and surrounding environment. Structural systems dwellers, or other context-based and environmental awareness and behavioral change. Instead, demographic and lifestyle changes conditions. The urban tall building of the merge with energy, lighting and facade environmental cues. will serve as major catalysts in the shift toward future fosters this innate quality, essentially systems to extend beyond the confines of CTBUH Executive Director Building Tall with Timber increasingly dense and vertical urban environments.

As the future of cities takes center stage, what Michael Green will we come to expect from the design and functions of the buildings within them?

The year 2050 will mark a generation of net-native adults who will have lived all their 05 Debating Tall: lives engaging with smart devices and materials. They will have experienced technological breakthroughs that will redefine how human beings interact – not only with each other, but with their surrounding Do Trees Belong on environment. We will live in cities where everything can be manipulated in real-time and where all components of the urban fabric are part of a single smart system and an Figure 1. Arup foresight future urban building. © Rob Skyscrapers? House Figure 3. Torre de Especialidades, Mexico City. © Alejandro Cartegena CTBUH 20 | Sustainability/Green/Energy CTBUH Journal | 2013 Issue III CTBUH Journal | 2013 Issue III Sustainability/Green/Energy | 21 06 Global News 50 Special Report: Highlights from the CTBUH CTBUH 2013 International Global News archive Façades Conference – London 26 The Use of Stainless Steel in Second-Skin Façades no maintenance and there is an expectation building security and safety by providing of at least 50 years of service. visual barriers. Exterior walls are being transformed from relatively simple climate-defensive Bioclimatic second- Bioclimatic Second-Skin Façades In fixed, woven meshes, perforated panels, or mechanisms to more active membranes that screen weather to reduce Rachel Coleman, Sian Disson, louvers, several factors influence the solar “skin façades are energy requirements. Innovative designs are being used on award-winning Bioclimatic second-skin façades are typically shading benefit and natural interior lighting projects around the world, and these concepts could be applied to a much between 0.2 and 4.5 meters away from the levels, the opening size, solar reflectance and typically between 0.2 broader range of buildings. Bioclimatic architecture refers to designing environmental barrier. The intermediate space transmittance influence the solar shading and 4.5 meters away buildings to improve thermal and visual comfort. These designs incorporate can be used to moderate heat, light, wind, benefit and natural interior lighting levels. Robert Lau & Daniel Safarik noise, pollution, and other environmental Therefore, seasonal daylight modeling is Catherine Houska systems that provide protection from summer sun, reduce winter heat loss, from the stresses. This space can provide shading, light necessary for design optimization. In climates and make use of the environment for heating, cooling, and lighting buildings. Author and air redirection, thermal load balancing, where the sun angle significantly changes environmental barrier. Catherine Houska, Senior Development Manager and resistance to heat loss and gain. with each season, fixed louvers may allow TMR Consulting Long before central heat or air-conditioning, second skin to achieve the building’s energy sunlight to enter in the winter, while reducing The intermediate 3209 McKnight E Dr. mankind modified building designs to suit reduction goals. European and US research The building inhabitants’ connections with heat gain in the summer. Pittsburgh, PA 15237, United States the climate and achieve natural cooling or has improved the ability to model the screens’ their surroundings are improved by these space can be used to Case Study t: +1 412 369 0377 e: [email protected] improved heat retention. The practice of potential benefits. This article will discuss new designs. The inner environmental barrier wall www.tmrstainless.com moderate heat, light, screening exterior façades from sun or winter modeling developments and illustrate how frequently has operable windows or provides Active Second-Skin Façades storms is an old concept that has regained several types of exterior stainless-steel other provisions for ventilation. The second CTBUH Report: Catherine Houska wind, noise, pollution, 56 Catherine Houska is an internationally recognized skin at least partially shades the inner wall, There are many variations on active second- popularity with growing international interest weather screens are being used on award- expert on the architectural applications and atmospheric corrosion of stainless steel. She consults in bioclimatic design concepts that better winning and innovative hybrid bioclimatic reducing summer cooling requirements while skin façades, but they are typically operable and other on new projects, provides forensic evaluations, and harmonize buildings with their environments. façade projects around the world and still allowing daylight to enter the building. metal louvers, wooden slats, or perforated consultants for numerous international industry associations. These concepts can be important tools in explores the potential for application of During the winter, these outer second skins panels supported by stainless-steel tension environmental achieving energy-consumption reduction bioclimatic façades in high-rise buildings. can shelter the inner wall from winter storms, systems or frames. All have integrated Modular on the Rise Houska is the author of over 150 articles and papers, 12 The Bow, Calgary and speaks regularly at conferences and workshops goals, while transforming exterior walls from while allowing the sunlight to enter and warm computer-controlled mechanical systems that stresses. around the world. She is active in standards relatively simple “climate-defensive” The emergence of whole-building life cycle up the building, lowering heating loads. work with the building’s heating and cooling development (ASTM A01 steel and E60 sustainability, ” CRSI and ACI) and represents the Nickel Institute at mechanisms into more active membranes. assessments (LCAs) as a sustainable design systems to respond dynamically to varying the USGBC. These screens are increasingly being used on tool is increasing awareness of the high Bioclimatic second-skin weather screens can conditions (Gonchar 2007, RMI 2008). was awarded a Gold-level German Certificate She holds a BS, Metallurgical Engineering & Materials larger structures. environmental impact of repeated material either be active, computer-controlled systems for Sustainable Buildings. Energy requirements James Barnes & Jonathan Science, Carnegie Mellon University and an MBA, Weatherhead School of Management, Case Western replacement and encourages specification of that constantly adjust to the environment or Sections of the shading system open or close are expected to be 20 to 30% below statutory Reserve University. Bioclimatic façade systems can consist of durable products that will remain in place low-tech, fixed passive systems. Here, we with changes in the sun’s trajectory or the requirements. The integrated computer- traditional overhangs and setbacks, but over the project’s service life. Stainless steel is focus on four screen types and provide both weather. This allows active second-skin façade controlled environmental systems adjust the increasingly a layer of screens is being placed a logical material for corrosive environments active and passive screen examples: systems to maximize the benefits of solar natural ventilation and sun-shading levels to Hendricks 58 CTBUH on the Road outside of the primary environmental barrier. with industrial pollution or salt exposure, radiation or lighting, minimize heat gain, or respond to changing weather conditions. These screens serve as a double envelope or particularly when there would be minimal to ƒ fixed and operable louvers; shield the inner wall during winter storms, When used with geothermal heating and ƒ woven mesh; reducing heat loss. Natural ventilation is cooling, the need for air-conditioning was ƒ perforated panels; and maximized to improve occupant health and eliminated, and winter heating requirements ƒ green (i.e., vegetated) façade screens. control building temperature levels. were greatly reduced (see Figure 1). CTBUH events around the Tension-supported systems, such green Energy is necessary to operate these systems, All the buildings are simple, glazed shapes screens and louvers, parallel the inner wall, and maintenance of the mechanical and made more interesting by their Type 316 while lightweight framing can be used to vary sensing systems is required. Active second- sunshade systems. Building Q2, the corporate the distance between the inner insulated skin skin façades have been particularly popular in conference and training center, has custom, world. and second skin, making seamless curving, Europe, Asia, and Australia, although some of perforated, passive sunscreens. Active geometric, and other shapes possible by the earliest examples are in North America motorized horizontal slat sunshades were using woven mesh or perforated panels. (e.g., Occidental Chemical Center, Niagara used on Building Q1. Motorized triangular, Falls, , completed in 1980). square, and trapezoidal fins were employed These second weather-screening skins can on Buildings Q5 and Q7. A dull abrasive cost-effectively reduce energy consumption ThyssenKrupp Campus blasted finish was applied to the outside, while improving the building’s appearance, at The TKQ architect consortium, consisting of while a highly polished finish was applied to a much lower cost than is possible through JSWD Architekten and Chaix & Morel, the inside of the slats and fins. Adjustment of Research modifying load-bearing walls (Murray 2009 & designed a seven-building corporate campus the slats’ angles determines interior light and Figure 1. Type 316 stainless steel exterior sunscreens in varying styles were used on the ThyssenKrupp corporate campus to actively adjust to seasonal and weather conditions to 2011). These façades can also enhance in Essen, Germany for ThyssenKrupp, which temperature levels. 58 Diary reduce energy requirements. © ThyssenKrupp AG Upcoming tall building events 26 | Façades CTBUH Journal | 2013 Issue III CTBUH Journal | 2013 Issue III Façades | 27 20 Imagining the Tall Building of the Future 60 Reviews Josef Hargrave & Ralph Wilson Review of new books in 32 History, Theory & Criticism Existing 100 the CTBUH Library Politics, History, and Height in Warsaw Under Tallest building height in 2013 height limits (in the background of the City m+ tall Planned Tallest building planned construction (rank in Europe) buildings UNESCO complex) and defining the maximum This paper describes the present high-rise boom in Warsaw, which is related to number and size of tall buildings in the city 360 m 339 m (1) 26 The Use of Stainless Steel in unprecedented development of the capital of Poland in the last 15 years and Moscow 93 23 8 Federation Towers – Vostok center. This is related to the so-called “visual Mercury City the spatial expansion of a high-rise zone created 40 years ago on the western Tower absorption capacity” (VAC) in relation to the 261 m (5) side of the city center. Today, Warsaw is ranked fifth in Europe in terms of the Istanbul**** 42 21 23 – cityscape. In a climate where the scale of tall number of high-rises and is considered the second-most preferred city in buildings is increasing every year, this analysis 306 m (2) London 38 6 44 – helps drive discussion about the future shape Second-Skin Façades Europe (after London) for high-rise investment (see Table 1). The contemporary of city panoramas, and the possible limits of Ryszard Kowalczyk Jerzy Skrzypczak Frankfurt 259 m (6) 369 m skyline of Warsaw combines the historic panorama of the Old Town complex (a 30 2 23 Warsaw landscape transformation. Comments UNESCO World Heritage Site since 1980) with a large cluster of modern sky- am Main Commerzbank 61 231 m (16) 320 m Paris*** 27 1 6 scrapers around the centrally located Palace of Culture and Science. For the Hermitage Plaza Tall Buildings as a Main Feature past five years, by using 3-D computer simulations, it has been possible for 237 m (18) 282 m Catherine Houska Warsaw 17 4 20*+30** urban planners to design a future city skyline with new skyscrapers while Palace of Culture & Science Kulczyk Investment Tower Of the Expanding City Center Feedback on past maintaining visual protection of the Old Town silhouette. * Projects approved by City Hall (with land use conditions or in local development plans) ** Projects waiting for the decision of City Hall Throughout the history of the spatial *** Includes , the location of La Défense development of Warsaw, the city center was **** Considered to be part of Europe Wojciech Olenski Introduction will occur in the near future (see Table 2), as the always marked by the highest buildings and Table 1. European cities with the greatest number of buildings taller than 100 meters. Source: City of Warsaw next ten high-rises are planned here, half of towers visible in the panorama. In medieval documentation and CTBUH Center. Journal issues Authors The contemporary skyline of Warsaw, as seen which will exceed 200 meters in height. In total, times, the most important landmark of Warsaw Ryszard Kowalczyk, Structural Engineer from the waterfront of the Vistula River, is in the last seven years, developers submitted skyline was a Gothic cathedral with an University of Ecology and Management in Warsaw Name Architects Height Status Function Comments ul.Wawelska 14, Warszawa 02-061, Poland composed of two independent landmark plans for nearly 70 tall buildings. enormous 80-meter tower, which was captured t: +48 604 212 829 Kulczyk Silverstein clusters (see Figure 1): one is visible on the A. Wyszynski 282 m proposed mixed-use – on many historical drawings of the city skyline. 32 Politics, History, and Height e: [email protected] Properties Tower escarpment in the form of a historical The tower was a great engineering on the site of Intraco II Jerzy Skrzypczak, Architect silhouette of the Old Town, defined by church Digital Model of Warsaw Trade Tower Center J. Skrzypczak J. Jańczak 235 m proposed offices achievement, not only because of the height Biuro Projektów Architektury J&J Spółka z o.o. Tower ul. Zygmunta Glogera 3 lok.17 and palace towers; the other, located in the Cityscape Transformation but also due to very difficult foundation Palace of Culture Warszawa 02-051, Poland distant background is the New City with L. Rudniew 231 m 1955 office protected monument conditions. Unfortunately, after 100 years it was t: +48 22 823 10 38 and Science In Warsaw's Skyline e: [email protected] skyscrapers. The coexistence of two different For the evaluation of the city skyline, a destroyed by a hurricane in 1602. conflict with UNESCO Warsaw Spire Jaspers-Eyers Architects 220 m 2015 offices concentrations of building types, extending comprehensive urban elaboration was skyline Wojciech Olenski, Urban Planner 62 Meet the CTBUH Municipal Office of Town Planning and Development parallel to the river, is the defining characteristic developed in the Municipal Office of Town The first real high-rise that served as an office Strategy of the City of Warsaw feature of the Warsaw cityscape. Planning and Development Strategy of the Złota 44 Tower D. Libeskind 192 m 2013 apartments – building was the headquarters of the Swedish Pl.Defilad 1, pok.1319, p.13, Warszawa 00-901, Poland t: +48 22 656 65 19 City of Warsaw based on precise Warsaw Trade Majewski, Wyszynski, conflict with UNESCO telephone company Cedergren, also known as 208 m 1999 offices Ryszard Kowalczyk, Jerzy e: [email protected] Presently, the city skyline is changing its scale methodology, the consideration of different Tower Hermanowicz Architekci/RTKL skyline PASTa, completed in 1910 in the “Chicago and shape. This is most visible in the Western scales of perception of tall buildings and the InterContinental School” style. With its height doubling the T. Spychala 164 m 2003 hotel – Ryszard Kowalczyk is a professor at the University Hotel David Malott, Kohn Pedersen Fox for Ecology and Management in Warsaw. He has Center District (so called “Warsaw Manhattan”) use of a digital 3-D model of the city as a tool. width of the street frontage, the 55-meter compiled more than 60 years of research, consulting, – a special area with skyscrapers designed over 40 The virtual 3-D model of Warsaw was made in tower had an interesting quasi-historical façade and teaching in various universities and research Rondo 1 Skidmore, Owings & Merrill 159 m 2006 offices – institutes in Poland and overseas. He has also been years ago as a counterpoint to the domination of 2007–2008 by two specialized geodetics and and an observation terrace on the top. Skrzypczak & Wojciech Olenski a UNESCO expert for vocational and technical the controversial Palace of Culture and Science. In geoinformatics companies, using data from Cosmopolitan H. Jahn 159 m 2013 apartments – education in the Middle East (1983–1989). His main fields of research are: structures, dynamics of the last 10 years, the number of high-rises erected aerial photos and field measurements. The The first modern skyscraper in Warsaw was Warsaw Financial J.Skrzypczak J.Jańczak / KPF/ 2008: winner of Trane structures, and structural systems of tall buildings. in this area has doubled, and the height of towers digital model is compatible with the GIS 144 m 1999 offices built between 1931 and 1933 for the Prudential Center Epstein & Sons Showcase Building Award Jerzy Skrzypczak was an academic teacher and has increased by 50%. But the biggest changes software used by urban planners. Insurance Company and quickly became the supervisor of theses at the Technical University Prudential M. Weinfeld 69 m 1936 offices protected monument highest building in the city, and a symbol of of Warsaw from 1955 to 2002. Skrzypczak has won numerous awards and distinctions in urban modern Warsaw. At the time it was the planning and architectural competitions, including Cedergren / PASTA B. Brochowicz-Rogoyski 55 m 1908 offices protected monument second-highest building in Europe. Its elegant CTBUH Organizational Members the Distinguished Honor Award of the Association 63 of Polish Architects in 2005. Since 1998 he has been 66-meter tower was accented by stone façades. the general designer and partner of Biuro Projektów Table 2. The highest buildings in central Warsaw (including the oldest). It was built on a welded steel frame, one of the Architektury J&J Spółka z o.o. first such solutions in the world and was 38 Using Computational Fluid Wojciech Olenski is an urban planner for the The two main objectives of the analysis are tall buildings, enabling a decision process designed by Stefan Bryła, one of the pioneers City of Warsaw. Since 2007, he has specialized in protection of the historical cityscape and with regard to the buildings’ siting and height. of welded structures. Current reconstruction Structure & Member Listings city landscape modeling, with special reference to simulation of high-rise buildings in the spatial creation of a modern city center. Tall buildings plans calls for restoring the 1936 television structure and panorama of the city, and the are studied, both as architectural objects and Practical objectives of the analysis concern the station mast built on the roof of the skyscraper preservation of the UNESCO registered historical Dynamics to Optimize complex. He has elaborated a methodology for urban structures. The analysis allows limitation of existing and new skyscraper and destroyed in World War II. Both high-rises, evaluating the location and form of tall buildings. visualization and review of all newly proposed zones, subjecting some areas to mandatory PASTa and Prudential, have been preserved in Figure 1. Structure of the left-side panorama of Warsaw seen from the Vistula River. © Wojciech Olenski Tall Building Design 32 | History, Theory & Criticism CTBUH Journal | 2013 Issue III CTBUH Journal | 2013 Issue III History, Theory & Criticism | 33 Ahsan Kareem, Seymour Spence, Enrica Bernardini, Sarah Bobby & Daniel Wei We have a ‘wood first’ policy in British Columbia, “where public buildings have to consider the use of wood first and effectively prove why they can't use wood in the building design in order to proceed.

Michael Green, page” 46

CTBUH Journal | 2013 Issue III Inside | 3 Talking Tall: Michael Green Finding the Forest Through the Trees: Building Tall with Timber

The pursuit of new technologies for building tall has fostered a new perspective on one of mankind’s oldest building materials: wood. Through research such as the recently-published The Case For Tall Wood Buildings, architect Michael Green has been singing the praises of using mass timber to build tall structures for years, and has just broken ground on what will be the tallest wood building in North America. Green spoke with CTBUH Michael Green Editor Daniel Safarik about the critical role wood will play as a practical and sustainable building material in a dense urban future. Interviewee Michael Green, Principal How did you develop an interest in The role of tall buildings as icons for their Michael Green Architecture 57 E Cordova Street pushing the limits of building tall in wood? communities is an interesting one. It creates a Vancouver V6A 1K3, Canada It comes from building with my grandfather in competitive spirit between communities, t: +1 604 336 4770 e: [email protected] his shop as a kid. He loved to woodwork. I've allowing us to push the limits. www.mg-architecture.ca been around wood all my life. What made you think about building tall Michael Green Michael Green is dedicated to bringing attention Later, I was working for Cesar Pelli, and we with wood? to several of the overwhelming challenges in were doing things like the Petronas Towers. I I started building more and more with wood, architecture today. The first is climate change and how the built environment is an enormous thought steel and concrete were interesting, realizing that it was an absolute land of contributor to the factors damaging the very but the innovations were just building on opportunity from an innovation point of view. environment designers and architects are seeking to improve. The second is the profound reality that previous engineering breakthroughs. over the next 20 years, 3 billion people, or 40% of About 10 years ago in Central Europe, the the world, will need a new affordable home. Michael believes in championing a shift to new ways of It was informative to see how inspired introduction of cross-laminated timber (CLT) building that will complement the intersection of communities became by building tall. I panels started to change the way buildings man’s greatest building challenges. watched the excitement in Malaysia about could be done at a larger scale. CLT is a great the Petronas Towers, and how that kind of product, but is really just one of many mass transformed the image of the country. timber panels that would allow us to really dramatically change the scale of what we can build with.

CLT is made by taking boards that can be 1x4s, or 2x4s, or 2x6s. These are laid down side by side, pasted with glue, and then another set is laid on top at 90 degrees, creating what is like a jumbo piece of plywood.

It creates a panel that has great inherent strength and allows you to use a wood grade that you would never use for structural material on its own, because it's of poor quality. When you start gluing it together in this way it gets the inherent benefit of this cross-laminated strength. So it allows us to use trees that are of a lower quality.

Why would we want to use lower-quality trees? In North America we are losing huge tracts of Figure 1. North Vancouver City Hall, Canada. © Michael Green Architecture

46 | Talking Tall: Michael Green CTBUH Journal | 2013 Issue III our boreal forests to the mountain pine beetle. say “that’s the future” is nonsense. Those are column plan for each floor plate, allowing it If you fly over British Columbia, Washington, great, interesting, fun stories, but that's not be an office building or a flexible residential Colorado, and Idaho, there are huge tracts of where the energy is. The energy has to be an building. dead trees. They typically go from being a deep urban environment. Big buildings are the green to red. The mountain pine beetle used to future. There's no question. So we needed to When we tested this theory, what we found is die off every winter because of cold. Now, kind of step back and say, “How can we build in that we got to 30 stories, and we actually just because of climate change, it's not dying off. So the future, using a rapid renewable, carbon stopped even trying to go higher, because we the beetle has just devastated the forest. sequestering material, at a big scale?” And mass knew people were talking about “tall” wood timber panels are what allow us to do it. We still buildings being 10 stories. CLT gives us a chance to use this otherwise are going to use glue-lam beams and columns, dead forest as a building material that but now we have the panels, and that means What is your major proof point? sequesters carbon. Otherwise, the trees just fall our floors can be built out of something Wood is significantly lighter than concrete. back to the forest floor and rot, releasing all the completely different. That means you're not fighting the types of carbon that they've ever sequestered during forces that you have in a seismic event, as you their life back to the atmosphere. Were there any precedents to your concept? would be with a heavier concrete structure. CLT platform construction has been done How do wood buildings “sequester” carbon? before, but that approach requires a whole lot The really rigorous work we put into the tall These are vast tracts of dead forest. And so of load-bearing internal walls and doesn’t do wood study was focused around important when you use them for forestry, that carbon well with lateral loads at height. It doesn't work questions. How is this going to work stays in that product, until we put it in a in an environment where you want lots of structurally? What's the market for it? What building and it burns, or the wood rots. As long planning flexibility. A developer doing a tower kind of flexibility do you need in a plan like I as it's in a protected building, it becomes a wants the freedom to say, “I want the walls just described to make this work in a real great sequestration vehicle. When you clear the here, or I want to grow this suite and shrink this marketplace? What's the cost of one of these trees then you're giving opportunity for new suite.” They don't want to be hemmed in by buildings, and how does that compare to trees to grow back and increase the return of load-bearing structural walls. So that became concrete? What's the carbon footprint, what's an otherwise dead forest. Today, it often ends an important goal for me. the energy footprint? What are the up being shipped to China, and used to make implications for envelope design, what are the formwork for concrete buildings. So, the idea How was your approach different? implications for acoustic design? that somehow we're saving trees by going with I wanted to show that tall office buildings concrete is completely not true. could be made of wood. To do that, we had to So we did The Case for Tall Wood Buildings to develop a whole new structural approach, say, “Here's why this makes sense and here are What was your breakthrough project with which developed into Finding the Forest the parameters for measuring it as a mass timber? Through the Trees (FFTT). successful solution.” The North Vancouver City Hall project is not a tall building, but uses laminated strand lumber I got together with Equilibrium Consulting, Has that led to projects? (LSL) in a really new way (see Figure 1). who are world-class wood engineers, and I said, I have a brand new 12-story residential wood Ironically, it came with the downturn in the “Guys, has anybody done world economy. The wood industry, which something like this before?” It's hadn’t been very focused on innovation, a very simple structure, but it realized they could sell the full panels. is really much more akin to balloon framing, where the Cross-laminated timber gives They lightened up their attitude, and then we walls go all the way through “us a chance to use this otherwise showed them what could be done. I was down and the floors are hung at Weyerhauser talking to their CEO and they're between the walls, rather than dead forest as a building just kind of waking up and going, “Wow, this is stacked on top of the floors. exciting.” material that sequesters carbon. That does two things. It Why did we not identify this opportunity dramatically reduces the Otherwise, the trees just fall earlier? shrinkage. And it allows us to To me, architects have been focused on the have these long vertical walls back to the forest floor and rot, future of sustainable building at a very in the cores, which creates this releasing all the carbon that suburban scale. You see a lot of straw-bale, great lateral bracing, and rammed earth and stacked containers. But to allows us to have an open they've ever sequestered…” CTBUH Journal | 2013 Issue III Talking Tall: Michael Green | 47 building project on Vancouver Island. And we that are wood-to-wood connectors, so not The truth is, when you start embedding all broke ground last week on what sounds like very much steel. Wherever we do use a steel your plates and using push-pin connectors, it's going to be the world's tallest wood piece to connect wood together, we actually you end up with just a little dowel that makes building, the Wood Innovation Design Center embed the steel connection in the middle of a dot of steel in the wood, holding it all (WIDC) in Prince Georges, British Columbia the wood, because a metal plate slapped on together. To me it's much more beautiful and (see Figure 2). the outside of the wood is actually the most elegant, and interestingly enough it's much vulnerable to fire. So we use the wood to more fire resistant, because the steel's hidden It's just short of 30 meters in height. It's got a protect the steel. That's critical to the success away. university program in the lower half, and it's of the project. technically only six stories, but it has a So, assembling a building in heavy wood mezzanine and a mechanical penthouse that That’s counterintuitive. with small steel connections actually puts it to that height, and the floor-to-floor It’s counterintuitive for a lot of people, but it's improves its fire rating? dimensions are really high, because it's an not unusual. It's actually a big part of the To make these towers work, we have to use academic building. success. We did it here in Vancouver over 100 two-hour fire rated assemblies. That would be years ago – we used to protect all the steel true of concrete, steel, or wood. It’s the same How is it being constructed? with wood. as those materials. We can meet all the code We're using some really innovative connectors requirements.

How are you dealing with objections? At some point, there may be some resistance from the steel and concrete industries if they start to get concerned that this is a competitive system to their market share. But I don't think that's based on science, I think that's based on a business market position. It's a matter of education, of using science, not emotion to carry the discussion.

My harshest critics are the architects in my own community. We have a thing here that's a little bit like what the Australians call the “tall poppy syndrome”: If anyone gets a little more attention than the next, then you've got to cut them down, right? So I get a little of that.

But interestingly enough, elsewhere in the world, everybody's been very positive about Figure 2. Wood Innovation Design Center, British Columbia, Canada. © Michael Green Architecture these ideas. I've been this year to Finland, Denmark, Italy, and I have upcoming trips in France and Belgium. You're seeing architects from these communities start to explore these If you are going to make more money by ideas.

“cutting down your trees to grow crops, you're So is code the real obstacle? Yeah, the building code is an obstacle going to do that. But if you are incentivized to because this is the first new way to build a tall re-grow trees and turn them into laminated- building in a hell of a long time. Of course people are going to go, “What? That's strange.” strand lumber you’re really talking about So I often say the hardest part of the job isn't the engineering, it's the managing of the farming buildings. We grow our food; the earth public perceptions of the issues, and it's education. And that applies to getting code has got to grow our homes as well.” authorities to understand the issues and to 48 | Talking Tall: Michael Green CTBUH Journal | 2013 Issue III get all of the scientific testing done to illustrate consider the use of wood first and effectively of the building industry, then who's going to how it all works. prove why they can't use wood in the building solve that better than an architect? design in order to proceed. Assuming the science works out, what We have to regain this role. And that means about cost-effectiveness? I’ve advised the government to change that to letting go of some of the preconceptions of Our FFTT system is one approach. And there a “carbon-first” policy. If you chose one industry what's possible. Just as the Industrial will likely be many more. It'll take us a while over another, you have a political problem. But Revolution shifted us so quickly from one way before we figure out the most cost-effective, if you chose “lowest carbon” as your top priority, of building to the next, we have to do it again. buildable and universal systems. But those will wood will automatically win. But also it's going come, just like they did with concrete and steel. to push the concrete and steel industry to The scale of the need is even bigger. But we improve their stories. can change in very short order. If you look at BTY Group, a cost estimator that worked with the evolution of the skyscraper, it's incredible us on The Case for Tall Wood Buildings, did a With a carbon-first policy, we can turn around how quickly it changed. Of course it's possible. whole cost section. It's really challenging, to developers and say, “If you choose to build a We need people to embrace the idea and because even figuring out which trades are wood structure, we'll give you a tax credit invest in the idea and get excited about it. going to do different portions of the work is based on carbon sequestered and density new. There is no trade for these kinds of achieved.” We have a significant carbon- In the future, we’re not just going to celebrate solutions, so there's real complexity in figuring reduction goal, in Vancouver in particular. As towers because they're a cool shape; we're out the costs. we move towards that, we're going to improve going to celebrate them because they actually the envelope performance of our buildings and have meaning again. It's an incredible But when we do figure it out, the big game- our energy performance dramatically. statement of a community to build a changer is speed. Wood building goes so much legitimately carbon-neutral building. Height is faster than steel or concrete. It allows for a Then, the material choices in building become amazing. It pushes our imagination and better life cycle, because you can actually that much more important. And that's why we creativity. But it has to be done for meaning, deconstruct these buildings really effectively need to be pushing this so hard right now, not just for aesthetics. and reuse these panels for centuries, which is even though it's not the biggest piece of the great. pie now, it will become the biggest piece. We’d It sounds like this could change the better have the answer long before it crosses economics of logging, too. In Vancouver, we're probably a few bucks over to being the biggest piece. Ultimately, the only way to reverse cheaper per square foot than doing the same deforestation is to change the value of the land building in concrete. It’s “cost competitive,” not And that's why I believe so passionately that under the forest. dramatically better. But when we got into other this is the time. This conversation would not be parts of British Columbia, we can be happening on these tall wood buildings if it If you are going to make more money by significantly cheaper. wasn't for climate change. cutting down your trees to grow crops, you're going to do that. But if you are incentivized to When you reduce the duration of construction How can architects help? re-grow trees and turn them into Laminated significantly, beyond materials and erection, Climate change has triggered a demand for us Strand Lumber you’re really talking about you have lower carrying costs for your to change the way we think. But the farming buildings. We grow our food; the earth construction loans and mortgage on the land conversation about “innovation” still seems to has got to grow our homes as well. and so forth. be about parametric modeling and BIM and shapes. It isn't about the fact that buildings are If that environmental case becomes a Over time, energy prices will go up. Every major 50% of the energy use and climate issues in business case, it could be the game-changer economist in the world will tell you we need to North America. This is why we as a profession you’re talking about. assign a cost to carbon, and yet we're are losing our credibility, because we're talking And that's why we have to start talking about it somehow politically unable to do it. If we are about pretty shapes, not about societal and as a thrilling opportunity. Not because we able to get our heads around that, then wood environmental benefit. Beauty is something we know all the answers, but because we've got to will become significantly cheaper than should do in our sleep as architects. get a lot more people excited about chasing concrete and steel. the answers.  Meaning is what we should be working hard What policy changes would help speed the for. That is what will rebuild our role in society, use of wood in tall buildings? because our role is, I think, the most potent Further Reading We have a “wood first” policy in British profession in the world right now. If half of GREEN, M. 2012. The Case for Tall Wood Buildings. mgb Columbia, where public buildings have to climate and half of energy is on the shoulders Architecture + Design.

CTBUH Journal | 2013 Issue III Talking Tall: Michael Green | 49