Thermo-regulating Future City Envelopes with Multivalent Surfaces

Cities are urbanizing and modernizing at alarming rates as populations leave rural areas for new opportunities in urban centers. Today global urban populations have surpassed their rural counterparts and are expected to continue to collect the bulk of global populations (UNFPA 2007). These future cities will be denser and hotter as the sheer volume of impervious surfaces required to meet the needs of urban populations replaces the natural ecological systems that previously regulated the local climate. As a result, temperatures within the urban core can exceed surrounding temperatures by as much as 10°C in what was previously considered to be temperate climates (NASA, 2005). Design for hyper-density means design for material density; hotter habitats require thermal sinking and the metabolism of solar energy that would normally be provided by flora. The majority of the urban growth is further projected to be in developing nations and will require low-maintenance durable envelope systems that mitigate variable solar resource in similar ways that used to be accomplished by natural systems as sustained ecologies.While the concern of modern cities focuses on envelope transparency as the social interface between users and their greater social and environmental context, the challenge of material intensive future cities will rest in the execution of opaque façade systems and activated surfaces that reintroduce thermo-regulative systems to an unyielding built environment. A new logic of receptive surfaces, intelligent articulation, and modified topology, while restoring as many of the functions of the original natural systems as possible, represents a new ecology reconnecting urban populations with the dynamic and fluid systems of the local environmental context. By engaging principles from bioanalytics, energy flows through the building enclosure are harnessed to metabolize excess thermal and environmental loads. These ‘energy exchange’ envelope systems harnesses bioclimatic energy flows through diffuse surfaces and opaque wall systems in order to reach a more effective thermal balance. The building façade is thus tuned towards ever changing localized environmental conditions through the use of multi-scalar color, texture, and morphology extended and augmented with next-generation technologies as they become available for widespread introduction. Through this versatile manipulation of material systems the envelope can then become a source of reclaimed space in the expanse of future cities for the introduction of these emergent built ecologies. In this paper, precedents will be explored and potential system manifestations will be discussed as the totality of the problem is characterized and quantified relative to changing local climate context and design adaptability. References1. UNFPA (2007). The state of world population 2007: Unleashing the potential of urban growth. United Nations Population Fund, United Nations Publications pp. 12. NASA/Goddard Space Flight Center Completed: 2005-05-16;Data Collected: 2001 http://svs.gsfc.nasa.gov/

Volume Editors
Anthony Abbate, Francis Lyn & Rosemary Kennedy

ISBN
978-0-935502-90-9