The Mitigative Potential of Urban Environments and their Microclimates

Cities play a crucial role in climate change: more than 50% of the growing population lives in cities producing most of the global GDP but also 78% of greenhouse gases (GHG) responsible for climate change. Moreover, due to their highly modified land-use and intensive activities, cities are at the forefront of the most rapid environmental and climatic change ever experienced by mankind. Yet, cities’ potential to mitigate both climate change and their own environment is underexploited. This paper explores ideas related to the potential of urban environments to modify their microclimates, reflecting on the overlapping potential between mitigative and adaptive actions. These actions in cities can not only tackle some of the largest contributing factors to global climate change but offer short- to medium-term benefits that could drive more immediate socioeconomic and behavioral changes. This review proposes and discusses a new preliminary definition of urban environments as microclimate modifiers—Mitigative urban Environments and Microclimates (MitEM)—and calls for further research into: (a) inter-connecting the full range of mitigative and adaptive initiatives already being undertaken in many cities and maximizing their input systemically; (b) developing a common and holistic definition of MitEM; (c) promoting its uptake at policy level and amongst the key stakeholders, based on its social and public value beyond the environmental

Resilient urban edges: Adaptive and mitigative design in Chennai

This paper investigates design responses to El Nino-mediated climatic disturbances, using the December 2015 Chennai floods as a test case. The effects of such disturbances are exacerbated by human intervention: urbanisation-led impermeabilisation of soil accentuates the urban heat island, makes water percolation difficult, increasing surface run-off. Using literature, precedents and on-site interviews with residents of a tenement block in severely-flooded Chennai, downstream of the River Adyar, key issues were identified. Additionally, impact of existing morphology on comfort conditions were derived using analytical tools of Envimet, Ladybug and CFD (outdoor) and TAS (indoor). The conclusions informed testing of hypotheses which merged with informal recycling practices of the residents. The paper discusses strategies employing recycled and local materials to build permeable surfaces (water-air-ground interfaces) to be embedded into existing architectural objects (by retrofitting), or utilised to build new experimental floating structures complementing the existing. The design studies show how strategies bring extreme temperatures of 42°C within a comfortable range in indoor and outdoor spaces; whilst contributing to flood mitigation. The paper speculates upon a resilient live-work environment for 2050 employing productive self-build networks to alleviate socio-economic polarisation characterising riverfronts, contributing to urban permeability and responding adaptively to daily, seasonal and extreme event

Contemporary Passive Shelters: Change of perspective, environmental diversity and contemporary lifestyles.

Currently, buildings use large amounts of their operational energy to counteract the impact of the external environment on their inhabitants. Recent years have seen a progressive attention on these themes due to the great energy saving potential of the sector, moving towards an integrated design approach between the building and its plants. Nevertheless buildings, although more efficient, are still conceived as containers of mechanically controlled microclimates. However, today, technology and new theories of comfort allow a radical rethinking of how buildings are conceived, designed and inhabited. This paper reports on a design research that investigates alternative models of habitable environments, proposing an original concept and role for buildings. The research aims to contribute to the discourse on new highly efficient buildings showing how an innovative design process based on the integration of adaptive comfort theory, building physics and thermodynamic principles, passive strategies and centrality of the user, can not only deliver less energy intensive and more comfortable buildings but also enhance the generative potentials of new forms and spaces towards a more contemporary and sustainable built environment

Bioclimatic and Regenerative Design Guidelines for a Circular University Campus in India

To transform the negative impacts of buildings on the environment into a positive footprint, a radical shift from the current, linear ‘make-use-dispose’ practice to a closed-loop ‘make-use-return’ system, associated with a circular economy, is necessary. This research aims to demonstrate the possible shift to a circular construction industry by developing the first practical framework with tangible benchmarks for a ‘Circular University Campus’ based on an exemplary case study project, which is a real project development in India. As a first step, a thorough literature review was undertaken to demonstrate the social, environmental and economic benefits of a circular construction industry. As next step, the guideline for a ‘Circular University Campus’ was developed, and its applicability tested on the case study. As final step, the evolved principles were used to establish ‘Project Specific Circular Building Indicators’ for a student residential block and enhance the proposed design through bioclimatic and regenerative design strategies. The building’s performance was evaluated through computational simulations, whole-life carbon analysis and a circular building assessment tool. The results demonstrated the benefits and feasibility of bioclimatic, regenerative building and neighbourhood design and provided practical prototypical case study and guidelines which can be adapted by architects, planners and governmental institutions to other projects, thereby enabling the shift to a restorative, circular construction industry

Sustainable Conversion of historic buildings in Cuba: the case of Santo Domingo de Atares Castle, Havana

Recently, in the Cuban capital of Havana, a number of fortresses were given away by the Army for refurbishment and conversion to public functions. In the last two decades, there have been examples of refurbishment and conversions of fortifications in museums, some of them with dire consequences for the collections and the structures. In this type of structure every architectonical element has historic value and very few interventions are allowed. However, the accommodation of modern functions and the preservation of the structure heavily rely upon the balance between various environmental parameters of the interior spaces. This study explores the challenges and opportunities of an environmentally driven conservation approach to the refurbishment of one of Havana’s most iconic XVIII century’s defensive structures, Santo Domingo of Atares Castle. The paper illustrates the development of an architectural proposal for the conversion of the castle into a museum and associated energy and environmental strategies. The museum function is particularly demanding due to the rigorous standards for the preservation of the collections, generally accomplished by mechanical equipment. Recently, however, there has been a major concern in the conservation scene about energy consumption and sustainable practices in this type of buildings. Therefore, the work identifyies the characteristics of the existing climatic and environmental conditions affecting the interior spaces of the thermally heavyweight fortress. This has led to an analysis of the requirements of the collection in a hot-humid climate in conjunction with the parameters for human comfort, in order to identify to what extent the original conditions can be passively modified to adapt the building to the conversion. Finally, with the help of computational dynamic simulations, passive strategies and zoning options were tested for the achievement of suitable interior environmental conditions and subsequent energy savings

Sustainable retrofit for flooding resilience

In recent years, the frequency and impact of flash floods in Mediterranean coastal towns has substantially increased and will continue to rise due to a combination of Climate Change and anthropogenic factors. In 2007, one Spanish town was tragically affected by the Girona River floods, which in few hours severely damaged and destroyed entire buildings. However, despite the severe psychological, physical and economic loss that the population suffered, there is insufficient information and awareness on the risks of recurrence of this phenomenon and the threat that it represents. Previous research studies have proposed to free the riverbed by demolishing buildings and create more green areas. However, an architectural and environmental design approach to retrofit and adapt the damaged housing in order to improve their resilience to extreme climatic events, has never been proposed. The aim of this project is to identify sustainable adaptation strategies for the design and construction of housing buildings affected by the floods. The following studies demonstrated that a series of mitigative and adaptive strategies can be successfully applied not only to prevent flooding and water ingress into building, but also to improve interior environmental conditions in order to maximise comfort and minimise heating and cooling energy demand

Sustainable architecture and social engagement for flooding and drought resilience

Climate change is disrupting our planet’s natural cycles and the steep socio-economic growth together with rapid urbanisation are increasing the uncertainty of its effects. During the last decades, frequency and impact of flash floods and droughts in Mediterranean and Middle-East regions has substantially increased and will continue to rise due to these new variations. Therefore, buildings and local architecture in these areas must be adapted to avoid future damages. However, disaster prevention will not be truly effective until the ‘human factor’ is considered, based on actual evidence instead of theoretical assumptions. Better research into how communities are affected by disasters and how they re-act with new architectural solutions is urgently needed. In 2007, one Spanish town was tragically affected by the Girona River flash-floods and its population and buildings were severely disrupted. This case study was chosen as the main testing ground within this research, whose main aims were: a) to identify environmental retrofit strategies to increase resilience and adaptation to flooding, while improving comfort and living conditions; and, b) to present the proposed strategies to the affected local population. The project revealed insights in the increased level of acceptance and understanding of innovative solutions by local inhabitants when greater communication and participation is achieved

What heavy weight buildings in hot climates can tell us about their thermal performance

Concrete, masonry walls and stone finishes are high density materials and have high thermal capacity, they are referred to as heavy-weight construction or thermal mass, which is the main construction type in Lebanon. Although thermal mass construction is usually recommended in hot climates in order to reduce internal temperature fluctuation, its actual thermal behavior in Lebanon is not well documented through direct observation, relying instead on its theoretical performance. This study’s main objective is to characterize the actual thermal performance of such construction, in the context of building occupancy and intermittent A/C usage. The paper starts with a brief introduction of the residential typologies in Lebanon followed by the description of the three thermally monitored apartments, in use or empty, located in one same neighborhood of Beirut, Lebanon. The monitoring was undertaken during summer 2015 using hourly data loggers. The analysis of the recorded data provides a clear and empirical understanding on: 1. how heavy weight buildings interact within the hot and humid climate of Beirut; 2. how the effect of regulating the internal thermal fluctuation is shown; and 3. what are the most influential factors that would further enhance thermal performance of thermal mass construction

The Mitigative Potential of Urban Environments and Their Microclimates

Cities play a crucial role in climate change: More than 50% of the growing population lives in cities producing most of the global GDP but also 78% of greenhouse gases (GHG) responsible for climate change. Moreover, due to their highly modified land-use and intensive activities, cities are at the forefront of the most rapid environmental and climatic change ever experienced by mankind. Yet, cities’ potential to mitigate both climate change and their own environment is underexploited. This paper explores ideas related to the potential of urban environments to modify their microclimates, reflecting on the overlapping potential between mitigative and adaptive actions. These actions in cities can not only tackle some of the largest contributing factors to global climate change but offer short- to medium-term benefits that could drive more immediate socioeconomic and behavioral changes. This review proposes and discusses a new preliminary definition of urban environments as microclimate modifiers—Mitigative urban Environments and Microclimates (MitEM)—and calls for further research into: (a) inter-connecting the full range of mitigative and adaptive initiatives already being undertaken in many cities and maximizing their input systemically; (b) developing a common and holistic definition of MitEM; (c) promoting its uptake at policy level and amongst the key stakeholders, based on its social and public value beyond the environmental