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[MULTI-STOREY] JAMES LAW CYBERTECTURE CTBUH GREEN LEAF ENGINEERS JOHN WARDLE ARCHITECTS VERTICAL ARCHITECTURE STUDIO RIDER LEVETT BUCKNALL

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EDITORIAL

Welcome to the second edition of GLE. Our publication provides an outlet for built environment professionals to candidly address topics bandied in the pulp-press, to share their successes (and unburden their failures) within the industry.

In this second edition our authors refer to multi-storey development, sharing their experience, learnings, and proposing improvements on the status quo.

It is our belief that GLE will make a worthy addition to your professional library. Our hope is that it inspires you to evaluate your contribution to the built environment, and to validate or challenge your way of thinking.

We look forward to your comments, ideas and contributions.

Email your feedback to gle@greenleafengineers.com James Law

CONTRIBUTORS

[james law cybertecture]

Stefan Mee [JOHN WARDLE ARCHITECTS]

Stefan is a Principal of John Wardle Architects and is a design leader within the practice, having worked at JWA since 1994. He has worked on many projects recognised for their design excellence, having won international architecture competitions and national architecture awards.

The work of JWA has been exhibited at the Venice Architecture Biennale in 2006, 2008 and 2010.

Stefan’s particular interests extend from the relationship of the institution to the civic realm, the interior as a landscape for learning, working or living to the inventive detailing of large-scale projects.

On FORMULA

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John Tuxworth

[council on tall buildings and urban habitat]

Antony Wood has been Executive Director of the CTBUH since 2006, responsible for the dayto-day running of the Council and steering in conjunction with the Board of Trustees. Prior to this he was CTBUH Vice-Chairman for Europe and Head of Research. Based at the Illinois Institute of Technology, Antony is also an Associate Professor in the College of Architecture at IIT, where he convenes various tall building design studios. A UK architect by training, his field of specialism is the design, and in particular the sustainable design, of tall buildings.

21st Century Tall

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Rob Dickie

[Green Leaf Engineers]

John is a founding Director of Green Leaf. John passed the IStructE Part 3 Exam to become one of the youngest Chartered Structural Engineers.

John’s interest in cross-discipline skills saw him complete a year of Architecture and also MBA studies.

John has worked on projects by acclaimed architects including Ralph Erskine, Norman Foster and Richard Rogers. His collective exposure to multi-discipline delivery models and ESD principles contributes significantly to Green Leaf’s Vision.

John is very active in research and authoring technical papers, and also within Queensland University of Technology’s Schools of Engineering and Architecture as a sessional lecturer & tutor.

MULTI-STOREY — ADDING VALUE

Antony Wood

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[GREEN LEAF ENGINEERS]

Rob is a founding Director of Green Leaf. His career began in Zimbabwe, where his training and experience as an energy engineer pushed him to the cutting edge of a developing industry called building services. He has since worked in Europe, the Middle East and in Australia. He is highly proactive in incorporating sustainable aspects in projects of every type and scale, believing that a sustainability agenda is often the driver for lean, cost effective design. Rob has been a guest lecturer at London’s South Bank University and is an active contributor to industry journals, such as Construction Weekly and Australia’s Architectural Review.

TALL STRUCTURES AS SUSTAINABLE icons

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Widely respected as a modern visionary, James Law has won numerous international awards for architectural design and leadership, highlighted by the achievements of Young Global Leaders 2010 in World Economic Forum and CNBC International Architecture Awards during 2009.

Accredited by coining the notion of Cybertecture, James leads the charge in blending new materials and technologies within architecture, to pave the way for innovating the fabric of mankind.

In modern society

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Chris Abel [VAST – THE VERTICAL ARCHITECTURE STUDIO]

Chris Abel is the author of numerous publications of architectural history, theory and criticism, including two collections of his own essays, and has taught in major universities around the world. He is a recognized authority on the work of Norman Foster and was co-curator with Lord Foster for the international exhibition, Sky High: Vertical Architecture, at the Royal Academy of Arts in London in 2003, for which he also wrote the book of the same title. For further information see: www.chrisabel.com

HIGH -DENSITY URBAN STRUCTURES

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Mark Burrow [RIDER LEVETT BUCKNALL]

Mark is the Managing Director of Rider Levett Bucknall Queensland Pty Ltd, a position he has held since 2001. He has worked in the property and construction industry in Queensland since 1972 and was appointed a Director of Rider Levett Bucknall Queensland Pty Ltd in 1987.

During his career, Mark has been involved in a diverse range and size of projects throughout the Pacific Basin. This diverse background has enabled him to specialise in strategic advice, cost planning and management.

TALL BUILDINGS

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On FORMULA Stefan Mee [John Wardle Architects]

We have often introduced shifts in scale from the city to the personal in our high rise projects, understanding that they are read within the cityscape ..., in the middle distance ... and up close (where you can interact in detail with it as user, visitor or pedestrian).

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I recently walked by a small housing project Il Girasole (“the sunflower”) in Rome, designed by the architect Luigi Moretti in 1949, and was

struck by the consideration given to the relationship of this private building to the public realm. Situated on an inner suburban corner, the street facade is singularly ordered, suspended above ground and then projected as the civic face that relates to the wider streetscape. A central vertical slot in the facade widens at the base to form an elegantly detailed entry courtyard that celebrates the threshold into the private realm. Along its sides the form breaks down into a more sculptural expression of the ten apartments within. At ground level the stone detailing is intimate and personal, designed to engage the passerby in material, texture and pattern.

A niche on the side street includes a sculpted stone leg wittily propping up the opening, as if by happenstance it incorporated an historical Roman fragment.

Il Girasole stood out from many similar apartment buildings nearby, unremarkable and formulaic in their design. Contemporary high rise projects, whether they contain apartments or offices, are generally driven by formulas. The repetitive nature

of the building type lends itself to establishing industry formulas to minimise risk and maximise the profitability of every project. These formulas include apartment templates that maximise yield, facade-to-floor area ratios that minimise envelope cost, material systems that are suitable to large scale work, structural grids that maximise efficiency, nett to gross floor area ratios, apartment mixes to suit the demographic nature of the target market, and so on. Many of these rules-of-thumb are lessons hard won through experience and are best accepted as a design constraint. Yet, it is very easy to find yourself irresistibly drawn toward a formulaic design response in this environment, under the ‘blowtorch of commerce’ as a slightly gleeful construction manager once described it to me. As an architectural practice, John Wardle Architects (JWA) have found it important to understand these formulas, why they exist, and then how some might be challenged to improve design outcomes whilst still meeting the underlying requirements of our clients.

Il Girasole, Rome, Italy

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The QV1 project in Melbourne (undertaken

by JWA in joint venture with NHArchitecture), challenged the rule of maximising repetition in apartment layouts, asserting the proposition that if we introduced some variation and stacked six floor plates with differing end apartments, these frayed ends would emulate the stacking of individual houses. In this way, the building dramatically cantilevers space for living into the civic realm as dining rooms jut toward the State Library forecourt and over Russell Street. At its heart the building obeys the formula for tight, well planned repetitive apartments which allowed for a loosening of the strictures of well worn apartment templates at each end.

At Dock 5 (undertaken with Hassell), in Melbourne’s Docklands, the tower is capped with two double height penthouse apartments that wrap around and conceal the mechanical plant room, making for an inhabited crown. At ground level, an artwork using woven marine rope by Dani Marti is cast into a lengthy ribbon of concrete wall that converts conventional entry into public gallery space. Leftover volume below a scissor carpark is fitted out to provide a wine storage facility, unasked for in the brief, and a tasting room theatrically entered from the foyer. This recasting of convention invokes surprise and delight in the passerby or visitor.

In a new office tower at 85 Castlereagh Street in Sydney (undertaken with Westfield Design and Construction) formula dictated a 9m gridded structure in a rectangular footprint for workplace efficiency, however such a structure would not fit this site. An elliptical plan was devised with an end core to the west which maximised yield whilst not detracting from the adjacent Sydney Centrepoint tower. In this case, the unusual footprint will undoubtedly prompt unconventional responses

within its interior. The public entry spaces for this project commingle with the retail spaces below, differentiating themselves with a monumental screen of varying profiled timber battens. In this instance, it is through the detail that a generosity to the civic realm is conveyed.

We have often introduced shifts in scale from the city to the personal in our high rise projects, understanding that they are read within the cityscape (in silhouette or profile), in the middle distance (collaged with surrounding built fabric) and up close (where you can interact in detail with it as user, visitor or pedestrian). In the Urban Workshop (with Hassell and NHArchitecture), JWA turned the ground plan inside out, demarcating the commercial foyer with a re-imagined historic laneway; creating a ‘sitting room’ upon entry called the Urban Table for waiting, meeting and catching up for coffee; and, inventing a fine grain of new lanes and piazzas across the site. The tower façade above incorporates patterning that can be understood at many scales. The overall effect is of a layered woven fabric, within the depth of a curtain wall that uses standard systems.

Conventional wisdom evolves slowly. As an example, high-rise projects are now designed around interior workplaces or apartment layouts rather than car park structural grids. Another is the changing demographics of apartment living - more singles and more extended families, with fewer empty nesters. Not every formula can or should be overturned, nor every convention dismissed.

Interestingly, within the specifically tailored exterior envelope of Il Girasole the apartment planning is formulaic, meeting conventional market expectations of the time. In the end, Moretti knew what to accept, when to challenge conventional expectations and where to intervene with new ideas.

John Gollings® QV1, Melbourne, Australia

John Gollings® Dock 5, Melbourne, Australia

85 Castlereagh Street, Sydney, Australia

TRENDS & CHALLENGES IN 21ST CENTURY TALL Antony Wood [COUNCIL ON TALL BUILDINGS & URBAN HABITAT]

It will take time to reach a satisfactory state of evolution in both energy and cultural terms, however I genuinely believe we are heading in the right direction.

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istorically most tall buildings seem to have been designed either as simple vertical extrusions of an efficient floor plan, or stand-alone pieces of high-rise urban sculpture. In these cases the main relationship with the urban setting either relates to commerce or the pure aesthetic, with the structure usually dominating the surrounds. This has led to the pattern of tall buildings as ‘isolationist’ architecture – standalone, non-site specific models that are readily transportable around the cities of the world.

This, in turn, has served to create a disconcerting homogeneity across global urban centers – a creation of a ‘one size fits all’ which in some locations may even displace centuries of local heritage. A skyline full of sculptural high rise may quickly establish an internationally recognisable visual character, but that does not necessarily mean it is inspired by, or relates at all to the location. This is especially true of cities in developing nations, where all things ‘Western’ are often perceived as progressive and modern. Thus the vast majority of tall buildings internationally follow a standard template of the rectilinear, air-conditioned, western ‘box.’

There is also debate with respect to tall buildings as a sustainable building type. Many actually consider the typology to be anti-sustainable, and the ‘Shortfall of Tall’ is that many are contributing to the degradation at both the local (cultural) and the global (climate change) levels. The main challenge for this building typology in the future is thus to create structures that are relevant to the specifics of

place – physically, environmentally and culturally. To do this, we need tall buildings that maximise their connection to the city, the climate and people.

The following eight principles are offered for consideration in the design of future tall buildings:

1. Variation in Form with Height Tall buildings should not be monolithic vertical extrusions of an efficient floor plan, but rather should vary in form with height. This variance in form should be inspired by both the building program internally and physically and environmentally with respect to the city externally.

A tall building could be considered as a number of stacked communities or horizons, with each horizon having a different potential to relate to aspects of the site/city. The external climate is not the same throughout those horizons (the Burj Khalifa is several degrees cooler at the top of the building than at the bottom) so neither should the form and skin be monolithic in response to this stratified climate. Similarly, a tall building potentially has a visual relationship with many places far and wide in the city at differing horizons within its form; a visual dialogue with these distinct places (and other buildings) can help describe a variance in form to further connect the building to its locale.

2. Variation in Texture & Scale There should also be a variance in skin and texture throughout the building. The concept of scale should be introduced throughout the building—a tall building could be thought of as a number of small buildings placed on top of each other within an over-arching framework of structure, systems, aesthetics, etc, rather than one extruded, monolithic form inspired by a single plan.

3. Revised Functionality Traditional paradigms for tall buildings should be challenged to increase the usefulness of the typology in sustainable cities of the future. This challenging of program should occur on two levels: (i) the type of functions that are traditionally

accommodated within tall buildings, and (ii) the number of functions that are accommodated in a single tall building. Tall buildings have the versatility to accommodate uses other than the standard office, residential and hotel functions that currently predominates. We could see the incorporation of functions such as sports, say utilising an external solar control skin as a rock-climbing wall, or agriculture. In addition, cross-programming/mixeduse within tall buildings should be encouraged to provide opportunities for more sustainable activity patterns (dualities of car parking, support functions, servicing, etc.) as well as variance in design and diversification of urban form. The challenges of climate change require us to intensify every expenditure of carbon—we need to enable multiple uses to every element created.

4. Communal Spaces.

Social Sustainability on an urban scale is a major challenge for our future cities. More open communal and recreational spaces (internal or external, hard or landscaped, large and/or small) need to be introduced into tall buildings, rather than an insistence on the maximum financial return on every square meter of floor space. Such spaces have been proven to improve the quality of the internal environment which has an impact on saleable/rental return, satisfaction of occupants, productivity of workers, etc. In addition, the inclusion of these spaces will make tall buildings more suitable for socio-economic groups often marginalized from tall buildings through the lack of such vital spaces where a sense of community can develop—families, the young, the old, etc.

5. Envelope Opacity Tall Buildings should be designed with more envelope opacity, as opposed to all-glass transparent boxes requiring significant shading devices to control excessive light, heat and glare.

Although the impact on both internal day lighting and views needs to be considered, all-glass towers

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7. Skybridges

do not make sense, especially in intense hot, solar intense environments. In addition, greater façade opacity gives an opportunity for greater thermal mass to allow the envelope to be better insulated from external temperature and climate variations.

More opacity also gives the opportunity for greater façade variance and expression.

ground plane at high level, including the parks and sidewalks, the schools and doctor’s surgeries, and other public and civic functions. The ground plane needs to be considered as an essential, duplicable layer of the city which needs to be replicated—at least in part—at strategic horizons within and between buildings; not in place of the ground plane but in support of it.

It seems completely nonsensical that cities are making a push for ever-denser, ever-taller urban form, but allowing the ground plane to be the only physical plane of connectivity. Sky bridges have the potential to enrich both tall buildings and cities, improve evacuation options, and reduce energy consumption through allowing horizontal as well as vertical movement. Every tall building should be considered as a vital element in an overall, three-dimensional urban framework, rather than as a stand-alone icon superimposed on a twodimensional urban plan.

6. Organic Matter.

Vegetation should become an important part of the material palette for tall buildings, both internally and externally. The presence of vegetation will improve environmental quality on both the local scale (i.e., part of the shading/air cooling system of the building itself ) and the city scale (quality of air, reduce heat-island effect, etc).

It will take time to reach a completely satisfactory state of evolution in both energy and cultural terms, however as the global recession puts paid to some of the more excessive tall ideas of the past decade, I genuinely believe were are heading in the right direction.

8. Bringing up the city If cities are looking to concentrate perhaps ten or a hundred times more people by building tall, then we need to replicate the facilities that exist at the

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IN MODERN SOCIETY James Law [JAMES LAW CYBERTECTURE]

The Pad, Dubai, UAE — James Law Cybertecture

Mega-cities may be the most sustainable and environmentallyfriendly landscapes that mankind can inhabit.

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s the World population continues to increase, so too will the trend towards urbanisation and the creation of Megacities – having populations in excess of 10 million.

In developing nations, exploding populations have resulted in urbanised cities as people migrate, looking for the kind of economic opportunities that large numbers of people offer. Cities of China and India are prime examples.

What will these Mega-cities look like? And what is the best form for these cities to take with respect to function and sustainability? There are two ways for a city to grow: outwards (urban sprawl); or upwards (urban density). – and one of these is a lot more sustainable than the other. By considering the practical limitations of urban sprawl, inclusive of energy usage per capita, it becomes apparent that high-rise living is the optimal way to accommodate

tens of millions. Let’s consider why, and some of the factors essential to success.

Transportation The low-density suburban environment of an urban sprawl, in a developed country involves lots of driving. In fact it is highly likely your household will have at least one private vehicle, maybe even one per household member. And you have to drive everywhere because everything is so spread out.

You drive to the store to get milk, or a loaf of bread, or, if you’re like me, the eggs you forgot when you went to the supermarket in the morning. You drive to work, and you probably even drive to the gym.

Compare this scenario to high-density city living.

More than 80% of people living in Manhattan travel to work by foot, bicycle or public transport.

Expanding suburban sprawl and private car usage is not a sustainable solution to the transportation needs of Mega-cities. Transportation congestion, and congestion taxation) in an obvious sign of this.

Infrastructure Millions of people living in a high-density condition will not be successful without proper infrastructure in place. Public transportation must be effective., There must be adequate, power, water, drainage and sewage systems. Poor examples of

The Technosphere, Dubai, UAE — James Law Cybertecture

mega-cities are evident where the population has exploded but investment in infrastructure has not kept pace, with the Governments’ short comings glaringly obvious.

High-Rise Buildings High-rise buildings will play a crucial role in the ability of Mega-cities to accommodate the growing masses of a converging populous. This is happening and can be seen in the shift towards super-tall high-rise construction from North America to Asia and the Middle East. In North America super-tall buildings are typically offices, whereas in Asia and the Middle East super-tall buildings are more frequently mixed-use and residential towers. Further innovations in the use of high-rises will inevitably follow as the high-rise form evolves to meet the changing needs of society.

All of these elements, and likely more, must be executed in synchronization for the Mega-cities of tomorrow to meet the demands of increasing populations. If planned and managed correctly, the man-made environments and artificial landscapes of Mega-cities, may be the most sustainable and environmentally-friendly landscapes that mankind can inhabit.

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MULTI-STOREY VALUE ADDING John Tuxworth [GREEN LEAF ENGINEERS]

James Morris/VIEW Montevetro, LONDON, UK

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igh-rise structures appeal to that part in all of us which is drawn to the big, the fast, and the shiny, and I’ve been fortunate to have gained experience working with architectural practices of international acclaim - including Ralph Erskine & Associates, Pinzon Lozano, and the Richard Rogers Partnership. The structural aspect of this building type is clouded in mystique for most industry professionals, however I suggest in many cases it is far more difficult to undertake the analysis & design of a two-storey home. All of the same analysis aspects require address, however for the house there are often numerous load paths and discrete member types, multiple materials (timber, steel & concrete), proprietary elements, and complexity of connections and reduced redundancy therein.

Even with the individualistic monoliths divined by architectural greats, the key difference between multi-storey & other more urbane structures is often the construction process. Multi-storey construction techniques are by necessity very much driven by

the individual contractor. Aligning with a contractor’s experience, preferences, programme, and available equipment (most significantly formwork and crainage) is of utmost importance. There are a multitude of unique formwork systems available, however investment in a particular proprietary system including capital cost, knowledge and skillbase must be spread across multiple projects to ensure profitability - especially in a harsh economic climate.

Whilst structural consultancies often appear to win high-rise projects based on reputation, and/ or an existing relationship with the design & construct (design & build) contractor, it is the ability to provide innovative solutions with respect to construction and materials use, and the facilitation of sustainability targets, which is the test of added-value. As an example, the two-level penthouse apartments at Sir Richard Roger’s Motevetro in Battersea London are particularly wonderful spaces. Myself & the team at Waterman Partnership achieved clean lines, minimalist expressed structure, and slender

‘floating’ floor plates through the use composite members, glass floors and even stairs. We designed a composite column system throughout the twenty-plus floors. Structural steel circular hollow sections (CHS) were core filled with high-strength concrete, which was pumped from the base of each two-storey lift. Connections were discrete, and the columns were fire protected with intumescent paint, doubling as the decorative finish. This system provided high-load bearing capacity in a slender profile, and which negated the requirement for battening/plastering, etc, contributing to Net Floor Area across the development.

It is common sense that best-value outcomes are typically provided by a holistic consideration of both design & construction across disciplines however this is seemingly an ever elusive goal with in the industry. The late Ralph Erskine’s Greenwich Millennium Village is a master planned residential development on a brown field site adjacent the Millennium Dome (now called The O2) in London.

Far from the questionable sociological results of

Montevetro, LONDON, UK

the infamous Byker Estate at Newcastle upon Tyne (conceived by Erskine in the 1970s), Greenwich Millennium Village was recognised as the pinnacle of sustainable multi-residential design in the United Kingdom. Prior to the significant uptake of BREEAM – and a full decade before the introduction of the Australian Green Star Multi-unit Residential Tool - the project championed sustainable development through the adoption of measurable sustainability targets. One of these was the use of Supplementary Cementitious Materials (SCMs) to minimise cement usage. My team researched and established the maximum percentage substitution rates which could be achieved utilising Granular Ground Blast Furnace Slag (GGBS or GGBFS), at the time recognised as being up to 60%. Whilst championing this innovation, we identified the reciprocal limitations with respect to construction programme and efficient floor-to-floor cycle. Both GGBS & Silica Fume affect bleed, setting times & early strength gain of concrete in colder weather.

Even with heating blankets our reinforced concrete flat-plate floors were estimated to require 28-day back-propping during the London winter. Thus we scaled back our SCM percentage accordingly.

Our latest efforts at Green Leaf have realised the engineering design of the twin-tower, twenty-five storey Belamar Towers, by Panamanian architectural practice Pinzon Lozano. As a multi-discipline practice we were able to pull-out all stops to realise a fully-coordinated solution with respect to structure and building services. To suit regional requirements (and unheard of in Australia or the UK) we designed the floors as unbonded post-tensioned slabs. With BIM software interfacing and some effort we enabled all building services to be cast integrally within the thickness of the flat-plate floors. This facilitated elimination of battened plasterboard ceilings throughout each accommodation level.

I am not quite sure of the construction savings enabled by our efforts on this project; however I am certain it rendered our consulting fee cost neutral.

It would be great to have that opportunity on every project.

Katsuhisa Kida Montevetro, LONDON, UK

structural model | Belamar towers

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TALL STRUCTURES AS SUSTAINABLE ICONS Rob Dickie [GREEN LEAF ENGINEERS]

“THE ‘SILVER BULLET’ IS NOT IN THE ARCHETYPOLOGY OF THE HIGH RISE – IT LIES WITHIN THE CIVIC OBLIGATION THAT SOUNDS THAT BUILDING IN TRYING TO IMPROVE & BENEFIT THE WORLD WE LIVE IN. THIS ATTITUDE OF CONSTANT IMPROVEMENT WILL TURN THE HIGH RISE DEVELOPMENT INTO A BETTER BUILDING & THEREFORE HAVE A FAR SIGHTED SOLUTION TO URBAN SPRAWL & REDUCING OUR ENERGY FOOTPRINT.

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n vogue thinking is that building tall will deliver a greater long term sustainable outcome for a community. You don’t have to think much past transport in an urban sprawl model to understand why this makes sense. This is part of the solution and potentially to the slight detriment of ‘building better’.

One exemplar of this is the Eastgate office block in Harare. The architect - Mick Pearce – through a fascination with termites, has replicated their unique ability to cool their own environment in a building product that pushes the bio-mimicry boundary. With a substantially reduced capital cost and annual energy savings approaching 35%, the building saved $3.5m in the first 5 years.

With all buildings, creating a product that works in a passive state first has to be a more sustainable outcome.

Consider the Bahrain World Trade Centre. It’s three 29m horizontal wind turbines are designed to produce around 15% of the buildings annual energy consumption. Recognised as an icon for its show of sustainable jewellery, the cutting edge design that accelerates wind speeds for the turbines also must add an excessive load to the air-conditioning plant that has to deal with large quantities of the resulting infiltration has been deemed questionable.

Regardless, this show of sustainable innovation sparked a new way of thinking in tapping into the unique sustainable opportunities in building tall.

Pushing more people into one tall building provides the unique opportunity to increase a ‘better build’ per capita. This is not being done through improvements to the current building regulations, it is being done out of the sustainable show that forms part of all modern construction of a large scale. These days it is hard to find an iconic high rise that does not have a developer with some green credentials building it.

Bahrain WorlD TRADE CENTER

If avoiding transport is a large part of the argument for building tall, what about the energy consumption in the vertical distribution of food, water, waste, energy and people? In designing the 86 levels of residential for the Damac Heights project in Dubai a process of ‘peak lopping’ was used to design all of the services. The concept moves commodities slowly up the building and stores energy, water etc locally. The result is a vastly reduced capital cost of core building services. The end user consumption of these commodities was managed by low usage fixtures and fittings, and the ubiquitous tri-generation plant were the energy centres distributed at every 30 floors.

Zero carbon buildings or even net exporters are viable within low rise structures, perhaps within reach of a 15 story building. Therefore a zero carbon Brisbane before 2026 is a thorn in the argument that tall is sustainable. The reliance on a green infrastructure is of course crucial in delivering this agenda, the question is where to apportion the cost of the ‘green-ness’. Is it in the development of the solar farm in Windorah or to import hydroelectricity from Wabo in PNG and continue to budget for an infrastructure that cannot keep up with demand, or is it perhaps to provide the framework that incentivises the implementation of localised embedded generators within cities to minimise the impact of urbanisation on existing networks.

U-Bora Towers Business Bay, Dubai, UAE

We are currently working on two energy masterplans, one on the Gold Coast and one in Tripoli, Libya. The Tripoli project will have the more sustainable outcome as there is no framework in place that regulates how infrastructure charges or energy prices are apportioned. This correlates with the Hans Monderman concept of -no rules with the right incentive creates a better result than an overregulated system with the wrong incentives.

The ‘silver bullet’ is not in the archetypology of the high rise, it lies within the civic obligation that surrounds that building in trying to improve and benefit the world we live in. This attitude of constant improvement will turn the high rise development into a better building and therefore have a far sighted solution to urban sprawl and reducing our energy footprint.

EastGate Office Block, Harare, Zimbabwe

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Explorations into HIGH-DENSITY URBAN STRUCTURES Chris Abel [THE VERTICAL ARCHITECTURE STUDIO]

“unlike most experimental designs in high-rise architecture, in which tall buildings are still treated essentially as free standing sculptured objects, VAST projects typically give equal emphasis to both horizontal and vertical spatial dimensions as well as movement systems within linked, multifunctional structures.”

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n the 1960s and 70s a small but vocal number of American urban and architectural theorists, including Melvin Webber and Robert Venturi, responded to the prevailing rejection amongst critics of dispersed patterns of urban form by launching their own radical critique of ‘Eurocentric’ urban theoryi. Unlike the compact historical cities of Europe and elsewhere, they argued, the low-density American city had its own spatial, social and cultural logic - ‘community without propinquity’ as Webber described it - based on mass telecommunications and affordable private transportation. Their arguments were supported at the time by the availability of apparently abundant quantities of cheap land and fuel supplies, together with the evident social and aesthetic failure of high-density, high-rise projects around the world

VAST 2009, UNSW. Scheme for Barangaroo site, Sydney by Nor, Turner and Wang featuring elevated concourses, vertical farms and triangular arrays of wind turbines or sails.

VAST 2010, UNSW. Scheme for central park site, sydney BY CHEUNG & Poon featuring elevated concourses and greened hills and valleys.

Today we live in an altogether different era, the many challenges of which include not only rapidly depleting supplies of fuel and land and the drastic environmental consequences of low-density cities and private transportation systems, but also the increasing threats to food security raised by the loss of productive farm land to urban development.

As popular as the detached suburban dwelling still is, particularly in Australia, where the general population is, if anything, even more addicted to their automobile dependant way of life than North Americans are, the human race continues to build its cities the same way at its peril. We are compelled therefore, to rethink the basics of urban life and form, not merely for reasons of aesthetic or social ideology of the sort that drove those earlier debates, but as an urgent matter of survival.

The Vertical Architecture STudio (VAST) was explicitly created to explore alternative, highdensity urban typologies to meet the needs of a post fossil fuel age. Beginning in 1994 with an experimental studio in high-rise architecture at the University of Nottingham, UK, inspired by the earlier works of Norman Foster and Ken Yeang, VAST has since taken on a life and purpose of its

own. It has been run in its present form at the University of Sydney (2006) and the University of Nebraska Lincoln (2008), and was most recently offered as a graduate elective at the University of New South Wales (2009-2010). In keeping with urban strategies of densification, all VAST projects have been set within large brownfield sites close to mass transportation hubs already designated for high-density urban development. Amongst its distinctive features, a prime goal of VAST is the design of urban spaces at elevated levels equivalent in environmental and social quality to those normally found at street level. Accordingly, unlike most experimental designs in high-rise architecture, in which tall buildings are still treated essentially as free standing sculptured objects, VAST projects typically give equal emphasis to both horizontal and vertical spatial dimensions as well as movement systems within linked, multifunctional structures.

The outcome, as demonstrated in numerous published schemesii, has led to the discovery and identification of several new building and spatial typologies, the topological qualities of which are in many respects closer to the multi-dimensional features of cyberspace than to any more familiar

urban models. For example, a conventional urban node at street level might offer a choice of movement at the same level, whereas an urban node in a VAST project not only offers choices in the usual directions of the compass but also up or down in a complex 3D spatial matrix, the full understanding of which, as in cyberspace, can only be gained by moving from one multi-choice node to another.

Such innovations call for new terminologies as well as new forms of representation. Together with more familiar concepts such as ‘sky gardens,’ ‘sky bridges’ and ‘green walls,’ a prototypical ‘vertical garden city’ of the kind created within recent VAST programs might include: large scale ‘sky parks’; greened ‘hills and valleys’; ‘elevated concourses,’ and ‘sky lanes.’ ‘Suspended podiums’ spanning between tall structures also liberate public spaces and movement at street level and provide more space for parks and plazas above. Where conditions are favourable, as in the Lincoln and Sydney Harbour projects, integrated arrays of wind turbines have also generated their own forms and names, such as ‘wind harps’ and ‘sails.’

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GLE 02

[MULTI-STOREY]

VAST 2010, UNSW. Scheme for central park site, sydney by CHE, DAVEY & SANTOS featuring vertical farms and sky gardens at intermediate levels.

In addition to localized energy production, since 2008 VAST programs have also included a substantial amount of localized food production.

Unlike most designs for vertical farms, however, which require the building and financing of separate towers, the strategy adopted within VAST programs provides spaces for intensive methods of food production within dual or multi-purpose structures, thus spreading the capital costs over the whole development. As food shortages and rising transportation costs begin to affect planning policies, we can expect such functions to play an increasingly important part in vertical architecture, to the point where conceptual boundaries between urban and rural functions will eventually be eroded.

The issues and problems these programs attempt to resolve are, as their acronym suggests, vast.

However, while still in its infancy, the Vertical Architecture STudio offers a vision of vertical cities and urban life far removed from the assorted collections of attention seeking tall buildings currently dominating urban skylines.

Webber, M. M., et al eds., (1964). Explorations into Urban Structure. University of Pennsylvania Press.

Also Venturi, R., et al., (1977). Learning from Las Vegas. Revised edition, Cambridge, MIT Press. The title of this article is a repost to the first publication.

(2010). ‘The Vertical Garden City: Towards a New Urban Topology.’ International Journal on Tall Buildings and Urban Habitat, Issue II, pp. 20-30.

Also Abel, C., (2010). ‘Vertical Garden City; Mark IV.’ Architectural Review Australia, August/September, pp. 60-62. VerticalArchitectureStudio/tabid/648/ language/en-US/Default.aspx

More examples of students’ work from various VAST programs are displayed on the Council for Tall Buildings and Urban Habitat (CTBUH) website: http://www.ctbuh.org/Research/ DesignResearch/NB: The author claims the intellectual property rights for the Vertical Architecture STudio.

Apartment Services

Offices

Public Gardens

Residential Gardens

Upper Retail Bridges

i

ii Abel, C., (2006). ‘Vertical Architecture.’

Architectural Review Australia, August/September, pp. 138-142. Also Abel, C., (2009). ‘Vertical Garden City, Barangaroo.’ Architectural Review Australia, August/September, pp. 110-113. Also Abel, C.,

Vertical Farming

Retail

Residential

VAST 2010, UNSW. SECTION THROUGH SCHEME BY CHE, DAVIS & SANTOS SHOWING MULTIFUNCTIONAL SPACES, SK Y GARDENS & VERTICAL FARMS

THE COST OF CONSTRUCTING TALL BUILDINGS Mark Burow [RIDER LEVETT BUCKNALL]

“...a building which increases in height increases in construction cost per square metre.”

S

ince the Empire State Building completed construction in New York over 77 years ago, people the world over have been entranced by tall buildings and most specifically, building the world’s tallest tower.

Tall building projects are rapidly growing in size and number, particularly in Hong Kong, China and the Middle East, as well as some parts of North America and Australia.

The taller they are, the more people talk about them. Property developers want taller and taller buildings so they can attract tenants and buyers.

According to leading global property and cost consultant Rider Levett Bucknall, a building which increases in height increases in construction cost per square metre. A project which is constructed horizontally can run multiple teams at once, while teams work one after the other on a tall building project.

The group has been involved in many of the world’s landmark tall buildings which sit on the skyline of some of our major cities, such as the Q1 Tower and Eureka Tower in Australia, the world’s tallest residential buildings, and International Finance Centre Two (Two IFC), Hong Kong’s prestigious finance sector tower.

The firm undertook the initial estimating and cost planning role on these buildings or provided quantity surveying services. The company subsequently monitored the construction cost of the projects and predicted the cash-flow to finance the projects.

Value engineering at various stages of the projects’ design and planning stages was carried out in order to generate a design which met the clients’ needs in terms of functional requirements, quality, environmental standards, timing and cost.

DEFINITION When one talks of tall buildings, people almost always think of the overall building height and the number of storeys. In fact, the number of floors is not a good indicator of defining a tall building due to changing floor to floor heights between different buildings and functions.

A tall building is not just about height, but also about the urban situation in which it exists. In some cities, most of the tall buildings are located in a Central District or Business Centre, which is a place for condensing renowned product brands / finance & securities / commercial bank representative offices. Most of the Grade A / Premium quality tall office buildings are sited there.

According to the cost efficiency of a building due to tall design, Rider Levett Bucknall has summarised the key issues below:

FOUNDATIONS & SUBSTRUCTURE For buildings founded on bedrock with endbearing piles, the taller they are, the lower the per square metre foundation costs will be. However, the overturning moment of the buildings due to their height and the wind load imposed on the top sections of the buildings may drive up the foundation costs.

Another cost consideration is the methodology or construction sequence, like top down construction of the foundation and basement which is carried out concurrently with the super high structure to save overall construction time.

STRUCTURE The design of the structure which has to overcome heavy wind loads plays a very significant role in fulfilling the designer’s aspiration of a tall building. Usually the structure is designed as a combination of basic structural systems such as reinforced concrete core wall, structural steel frame, prestressed works and trusses.

Such a combination invariably results in higher structural costs. The physical constraints in building the structure also contribute to the high cost of the structure.

FACADE Not only the structure has to be capable of resisting wind loads, the facade system and its fixing accessories should also be able to withstand wind impact. In addition, the cost of the window cleaning system is higher than the norm as the system has to be tailor-made to overcome wind speed with the assistance of cast-in accessories.

FINISHES & FIT-OUT TO COMMON AREAS Although these elements are area related rather than building height related, the overall area unit cost is generally marginally higher than that of typical office buildings since internal finishes of tall buildings are generally at the uppermost end of the cost range to project the prestigious image of tall buildings.

VERTICAL TRANSPORT The cost of lifts in tall buildings is much higher than other standard buildings due to more lifts of higher speed. Some tall buildings are designed to have multi-zone lift systems with several numbers of lifts in each zone while others adopt the double-decker option. In a majority of cases, a shuttle lift system is adopted, taking the passengers to the mid or upper zone for transferring to the top zone.

BUILDING SERVICES In most of the cases, the building services systems of tall buildings are divided into separate zones, each with its own plant located on intermediate plant floors. With this arrangement, additional pumps and major plants are required for acting as transfer and for distributing services within such zones, resulting in higher costs.

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