The Environmental Performance of Tall Buildings

Joana Carla Soares Goncalves

• Publisher: Routledge
• Year: 2010
• Print ISBN: 9781844078127
• eBook ISBN: 9781136531309
• Topic: Arquitectura
• Subtopic: Sostenibilidad en la arquitectura

Tall buildings represent one of the most energy-intensive architectural typologies, while at the same time offering the high density work and living conditions that many believe will an important constituent of future sustainable communities. How, then, can their environmental impact be lessened?

This insightful book takes in:

• an overview of the tall building and its impacts (looking at cityscape, place, mobility, microclimate, energy and economics)
• design principles and the development of the sustainable tall building
• global perspectives (covering North and South America, Europe, the Middle East and Asia)
• detailed, qualitative case studies of buildings in design and operation
• the future for sustainable tall buildings.

Not simply another showcase for future utopian designs and ideals, the information presented here is based on hard research from operating buildings. Highly illustrated and combining analysis with solid detail for practice, this is essential reading for architects, building engineers, design consultants, retrofitters and urban planners interested in or working with tall buildings, and researchers/students in these disciplines.

1

The Tall Building and the City

Preliminary considerations on the tall building and the city refer to the arguments for and against the tall building and the related issues of density. In the 1990s, the debate about the growing trend of tall buildings was discussed within the domain of urban planning and urban design, with special references to the European context. Proposals for tall buildings (and clusters of them) that have claimed a commitment to socio-economic and urban revitalization, as well as sustainability goals, are primarily justified by the advantages of density – recalling models and variations of the compact city.

Throughout the 20th century, the tall building has been presented by a number of architects and planners as the ideal building typology for the construction of the modern city and the accommodation of population growth. Nevertheless, it was office use rather than residential use that was the motive for the boom in the construction of tall buildings in North America, first at the beginning of the century and again later after the Second World War. At the turn of the 21st century, the largest percentage of tall buildings was used for commercial business enterprises, followed by residential functions (Ali and Aksamija, 2008). In fact, the vision of the tall building as the residential building type within a consistent urban planning proposal to contain population growth was never realized.

The economic advantages of the tall building over the value of land have been the main driving force for the transformation of the built environment of entire cities, or parts of them, throughout the last century, creating the iconic places of modern times, such as New York City and Chicago. The construction of tall buildings is a pattern of economic development of the 20th century that will continue for decades to come in different parts of the world, in both developed and developing economies. Besides profitability over the value of land, the iconic force of the tall building often adds economic value to its vicinity, consequently attracting more development. However, this is a complex process of urban transformation, often misleading and creating places of poor urban quality and high energy demand.

Neighbourhoods of tall buildings are also related to busy urban environments and thriving socio-economic activities. In fact, in addition to the economic advantages associated with building tall, the socio-economic benefits of densification and intensification of urban activities have persuaded business communities around the world to rely on a network of interdependence and physical proximity. In other words, the economic success and popularity of business centres where the tall building is the main reference of the built environment, have raised interest in socio-economic vitality and urban quality created by density as well as in the image of the tall building around the world.

At the same time, the tall building is still a highly polemic building typology, with questions over our need for tall buildings and their power to act as a catalyst for urban regeneration. The idea of the power of tall buildings to promote socio-economic revitalization of degraded urban areas is based on the argument that the tall building can increase the value of land, making the surroundings more attractive to further development, bringing more investment and more tall buildings. Moreover, in degraded and underdeveloped urban areas, tall buildings are also associated with basic infrastructure and urban design. However, tall buildings can equally cause negative impacts on the built environment, if they do not carefully follow planning measures and a consistent urban design strategy for the insertion of tall buildings that responds to an urban and environmental agenda.

With entire financial districts being built in a matter of a few decades, the remarkable presence of tall buildings has transformed the urban form and ground conditions as well as redefined the skyline of entire cities, giving the tall building a prominent role in the urban form of the contemporary city. Comparing the current urban morphology of cities in Asia such as Tokyo, Hong Kong or Shanghai, with North American urban centres such as New York or Chicago, we can show the notorious increase in the height of tall buildings.

The arguments against the tall building are related to various concerns including building and city scales: disruption of local socio-economic dynamics, social exclusion, creation of poor quality urban spaces, drastic interventions in the city skyline, impact upon the environmental quality of the surroundings, high consumption of operational energy and maintenance costs, to name a few. However, all the listed negative impacts result from planning and design decisions and are not problems inherent in the typology.

When the design of a tall building does not contemplate the preservation of cultural and environmental assets of the city, including residential neighbourhoods and public places, these large enterprises become potential threats to the quality and integrity of the socio-economic structure of the city. This risk is relatively higher in cities of emerging economies, where the planning rules and urban growth are strongly influenced by market forces, with less control by the local authorities.

The tall building carries the advantages of density and proximity as well as the challenges and difficulties of integration into the physical and socioeconomic contexts of the city. Originally, the tall building was a poor typology for social interaction and urban integration. However, in clusters or alone, architectural and urban design strategies can reverse the negative impacts and actually create inviting and thriving public and private spaces. The way in which the tall building touches the ground and is inserted in the urban fabric is crucial for the preservation of the street environment and the creation of more ‘humanized’/inviting urban spaces, connecting the public and the private realms.

The increase in the number of tall buildings in the last decades of the 20th century in cities around the world, including European urban centres, and also the arguments for the ‘sustainable’ and environmental tall building, have called attention to the limits and challenges of the tall building and its various impacts on the city, including socio-economic vitality of the surroundings, urban mobility and microclimate. With special regard to the issue of urban microclimate, it is interesting to note that impacts of overshadowing and wind turbulence, which are negative for the ground conditions in temperate climatic conditions of cities like London, Frankfurt, New York and others, are positive in hot climates, supporting the environmental argument for the tall building in those cases.

The various impacts of the tall building upon the built environment highlight the importance of a critical view, considering planning measures and urban design strategies in order to contextualize the tall building. In principal, planning regulations are intended to protect the environmental quality of buildings and open spaces, among other important aims. In that sense, they have a fundamental role in controlling the environmental impact of tall buildings. The definition of plot ratio and floor area coefficients, as well as distances from the site’s borders, are usual topics of planning regulations, determining the morphological configuration of the urban fabric, but are not enough to cope with the environmental impact of tall buildings. Key urban issues related to the insertion of tall buildings are: where? How many? How far from each other? What programme of uses? And finally, how high?

In 2007, more of the world’s population lived in urban areas rather than rural places; this, together with the growing environmental impacts of cities has called attention to the strategic role of urban density within the broader discussion of urban sustainability.¹ Although the tall building is not a particularity dominant feature of big and dense cities, its contribution to the creation of compact urban fabrics and higher densities has been highlighted in urban design proposals for sustainable cities around the world, with regard to its great impact on occupation densities of land compared to urban sprawl and with regard to energy savings from more compact urban transportation. Nevertheless, the negative impacts of the tall building listed above are matters to be addressed in both urban and architectural design to achieve urban sustainability goals.

Despite discussion of the role of the tall building in more sustainable urban environments, it should be acknowledged that in the majority of the cases, the future of more sustainable cities does not rely on the tall building typology; sustainability is about density and urban design, and not about a specific typology. Nevertheless, the tall building will be present where there are economic interests, technological resources and political will. For this reason, it needs to be better designed in both urban and architectural terms.

The tall building and the argument for density: Historical precedents

Already in the first decades of the 20th century, visions and proposals to accommodate the population growth and the development of cities highlighted the role of the tall building typology. The ideas for the ‘new’ urbanism introduced the concept of the ‘compact city’, emphasizing the importance of density and proximity for the success of the modern city, while saving natural areas from the impacts of urban sprawl.

Alternatively, the future of the modern city was also envisioned according to a much more decentralized urban model, characterized by low densities and supported mainly by the growing popularity of the car culture. Frank Lloyd Wright was a believer in decentralization, whilst Le Corbusier proclaimed the centralization of the urban environment, seeing the compact city as the best model to respond to the needs and expectations of the emerging modern society, providing the socio-economic benefits of density, while rescuing the relationship between man and nature.

Interestingly enough, the two extreme and opposite positions, represented by Frank Lloyd Wright and Le Corbusier, were trying to respond to the same problems of the city of the industrial revolution, where insufficient urban infrastructure, compromised public health and low environmental quality were among the threats to the development of cities into the 20th century. Nevertheless, a major factor differentiates the environmental concerns with regard to the modern city of the 1920s and today: the threat of global environmental change caused by energy consumption and the consequential air pollution.

The compact city of tall buildings was advocated by Le Corbusier as ...

Table of contents

• Cover
• Halftitle
• Title
• Copyright
• Contents
• List of Figures, Tables and Boxes
• Foreword by John Worthington, Founder, DEGW
• Foreword by Klaus Bode, Director, BDSP Partnership
• List of Acronyms and Abbreviations
• Acknowledgements
• Introduction: Why Should We Consider the Environmental Performance and Urban Sustainability of Tall Buildings?
• 1 The Tall Building and the City
• 2 The Global Perspective
• 3 Towards an Environmental Approach
• 4 The Environmental Paradigm of Tall Buildings
• 5 Final Considerations: Lessons Learnt and Future Issues for the Environmental Tall Building
• Appendix: Design Exercises for the Environmental Tall Building
• Index