The research question
Can architecture and construction science influence the regional and global climate crisis and provide credible, scientifically sound and ethical solutions? Is it possible through the appropriate design of buildings, urban structures and other infrastructures to limit the emissions of greenhouse gases, decrease the temperature of cities, reduce the frequency and amplitude of extreme events and protect the health of well being of citizens? Based on solid scientific knowledge and evidence from thousands of large scale applications, the answer is a resounding yes!
Architecture, construction and climate change are strongly interrelated. Higher ambient temperatures and extreme climatic events increase the cooling energy used in buildings disproportionally to the corresponding decrease of the heating energy, while raising the concentration of harmful pollutants and negatively impacting indoor environmental quality and human health. Buildings are a significant contributor to global and local climate change. According to UNEP, the sector is liable for about 38 percent of total greenhouses gas emissions. In addition, buildings play a huge role in the creation of the urban heat island (UHI) phenomenon increasing the temperature of cities. Urban heat island is caused because of the inappropriate use of absorbing materials like black asphalt and dark exterior roofing materials, the high density of buildings reducing wind penetration, generated anthropogenic heat, a lack of greenery and water, and excess use of impervious surfaces that store solar heat then re-emit this back into the air. Urban overheating has a significant impact on energy usage and the environmental quality of urban space, increasing the ecological footprint of cities and raising the risk of heat related mortality and morbidity. It also seriously affects the quality of life of vulnerable and low-income households, increasing substantially indoor temperatures during extreme events and placing people’s health and life under threat.
Scientific studies estimate that because of regional and global climate change, the energy consumption of buildings by 2050 may double, and the temperature of cities may increase up to 4–5°C.1Subsequently, the concentration of harmful pollutants like ground based ozone may increase up to 50 percent, while heat related mortality and morbidity may raise up to 100 percent including the expected physiological and technological adaptation.2 In addition, heat related vulnerability and the exposure of low-income populations to dangerous climatic conditions may rise tremendously putting lives under threat.37
The role of architecture
Properly designed buildings benefit from low energy consumption for heating and cooling along with a superior IEQ or indoor environmental quality. Solar and heat protection of the envelope, amortisation of heat using thermal mass, dissipation of excess heat to natural sinks, appropriate natural ventilation rates, penetration of daylight, use of healthy and low-carbon materials, and green microclimates around the building can decrease energy needs by up to 80 percent compared to a conventional design. At the same time, such moves also improve thermal and visual comfort while decreasing the concentration of harmful indoor pollutants by 90 percent. A high standard of environmental performance in buildings is the responsibility of the architect and should be achieved through proper design and not by using additional engineering devices. The higher the size of the installed engineering systems to satisfy energy and comfort needs, the lower the success of the architectural design.
Architects are also responsible for mitigating the urban heat island effect. The use of additional greenery in cities, be it integrated into buildings or in the city infrastructure, along with the use of reflective and other advanced materials in open spaces and the exterior envelope of buildings, the use of water sources, solar control and shading of the open urban spaces, can reduce the peak ambient temperature of cities up to 3°C.4 Mitigation measures result in an impressive improvement of the outdoor thermal comfort levels, a reduction of up to 40 percentof the cooling energy consumption of buildings and, most importantly, a decrease of heat related mortality and morbidity by up to 35 percent.1 Revitalising the thermal environment of cities results in a substantial economic and social upgrade of urban spaces, generates wealth, promotes resilience and sustainability and creates employment. Regenerating urban space in deprived areas in this way helps to eradicate urban poverty and vulnerability, promote social equity and diminish economic disparities and discriminations.
While the technical potential to face the problems of global and mainly regional climate change seems to be very high, the economic, financial and social obstacles, as well as the lack of adequate policies, substantially reduces the global capacity of the architectural world to tackle the problem in a radical way. It is evident that the actual and future targets of architectural design should go beyond common practice and the simple satisfaction of national building energy codes. Instead, it should be driven by ethical issues, aiming to protect the health, comfort and wellbeing of dwellers and citizens while defending the local and global environment. The adoption and achievement of these objectives and practices requires planning and the need to follow a fully innovative scientific and political agenda full of technological breakthroughs and the implementation of advanced technologies and policies. Architectural interventions should be part of a proactive, rather than a reactive, agenda. Such a future plan will require substantial investment in the global building sector, including in cities and individual buildings, which will create widespread economic, scientific and social opportunities for the future and will certainly create major medium- and long-term benefits for society. In parallel, it will help to alleviate the intensity and the consequences of the problems faced by the low income and vulnerable citizens.
The climate crisis offers a tremendous new challenge for the architectural profession – to increase the added value of technological, economic and social interventions in the built environment and succeed to translate the climate challenge into a future opportunity.
– Mat Santamouris is scientia professor, Anita Lawrence chair high performance architecture at UNSW Built Environment.
1. M Santamouris, Minimizing Energy Consumption, Energy Poverty and Global and Local Climate Change in the Built Environment Minimizing to Zero the Building Sector (Elsevier, 2018)
2. M Sanderson, K Arbuthnott, S Kovats, S Hajat, P Falloon, ‘The use of climate information to estimate future mortality from high ambient temperature: a systematic literature review’ (2017), Plos One, 12(7): e0180369
3. M Santamouris and D Kolokotsa, ‘On the impact of urban overheating and extreme climatic conditions on housing energy comfort and environmental quality of vulnerable population in Europe’ (2015), Energy and Buildings, 98, 125–133, DOI: 10.1016/j.enbuild.2014.08.050
4. M Santamouris and D Kolokotsa, Urban Climate Mitigation Techniques (London, Francis and Taylor, 2016)