By Dr. Iftekhar Ahmed, Associate Professor – Construction Management/Disaster Resilience, School of Architecture and Built Environment, University of Newcastle, Australia

Historically, the large catchments in Asia such as those along the Ganges-Brahmaputra and Mekong rivers experienced floods as part of an annual water cycle, and different forms of flood-adaptive vernacular architecture have developed there over a long time, as discussed in my article in the Habitat book.1 In Vietnam’s Mekong Delta, buildings are constructed on the most elevated land or sites raised by landfills; houses have a platform inside or a loft for emergency refuge. In central Thailand in flood-prone areas, buildings are raised on stilts. In Bangladesh, settlements are built on mounds, and in very low-lying areas, buildings on stilts are constructed. These examples demonstrate the ingenuity and age-old wisdom of flood-adaptive vernacular architecture.

However, since the ‘great acceleration’ of socio-economic developments since the 1950s,2 various factors such as urbanization and population growth, and significantly, climate change have created challenges to harmony with the nature of vernacular architecture. For example, in my recent studies, it was found that in Thailand, even after the massive 2011 flood, houses are no longer built on stilts, even though people were aware and built an upper story to be on the safe side;3 thus, the adaptive practices are transforming. Additionally, the COVID-19 pandemic demonstrated our vulnerability to biohazards, exacerbated by the global escalation of human conflicts and related massive demographic transitions, financial instability, and inequality. It is a trend that may well continue and assume more threatening forms in the future, creating powerful pressures on the sustainability of vernacular architecture.

Climate change caused by human activity including the creation and operation of the built environment is one of the most serious challenges for vernacular architecture. Disaster after disaster induced by climate change, particularly floods, each more severe than the last one, presents a future scenario of uncertainty and one of the most critical challenges to vernacular architecture. Floods occur widely around the world and are the most common natural hazard. With our planet’s hydrometeorological variability brought about by climate change, floods have become frequent, more widespread, and extensive, and follow erratic patterns; places that hardly had a history of floods are suddenly experiencing them, for example in the desert city of Dubai this year.4

A key related challenge is the widespread aspiration for ‘modern’ buildings in contexts with a strong tradition of vernacular architecture; this was evident for example in my study in Vanuatu.5 While vernacular architecture there was tuned to local resources and natural hazards, ‘modern’ buildings built without codes and standards were easily damaged and posed a threat to human lives. The built environment develops from the interaction of a wide range of social, economic, cultural, political, and environmental factors. Pressures in any of these factors can lead to vulnerability of architecture, as the Vanuatu example, and indeed a similar global trend demonstrates. As societies aspire to modernize, tremendous pressure is placed on the natural environment. Vernacular architecture is closely linked to nature, draws inspiration from it, and uses natural materials. Yet its creation also has profound impacts on nature in multiple ways such as the removal of trees and vegetation, and together with it, biodiversity and ecosystems. With population growth and urbanization, some of these impacts can be irreversible resulting in negative effects on long-term human wellbeing. For example, even in my much earlier studies,6 it was found that a key natural resource for building vernacular architecture in Bangladesh, bamboo, was declining in supply because of human demand and over-exploitation.

We are now at a critical crossroads—how to translate the lessons of vernacular architecture in the modern context to deal with the challenges posed by climate change, such as floods. Disaster resilience of architecture is often understood as the physical strengthening of buildings; while that is important, improvement of non-structural elements is also necessary, for example, capacity building at both institutional and community levels, early warning systems, and strategies for evacuation and safe refuge. Strategic land use and spatial planning are essential—they allow for avoiding or reducing the exposure to disaster risks that arise from locating and building settlements, facilities, and infrastructure in high-risk areas. For example, with repeat floods in Lismore in Australia, it has now become apparent that people can no longer continue to live in the very lying areas, even though their houses were raised on stilts in response to previous floods—in the recent 2022 flood, the inundation was more than 14 meters.7 There are thus plans to relocate such communities.

Together with floods, there are other hazards that pose a risk to architecture and human settlements, sometimes occurring together or cascading. It is therefore important to understand the types of disaster risk in a certain area in order to design disaster-resilient buildings. There are many examples from around the world where vernacular architecture has demonstrated its resilience, but with climate change, the nature and extent of risk are changing, with multi-hazard situations emerging, presenting new challenges that test the age-old wisdom of vernacular architecture. It is becoming increasingly necessary for designers to understand these multiple risks and the complexity they present and strive to achieve a balanced approach to addressing them. Building codes in many countries cover hazards—these should be consulted and followed. However, for a vast proportion of the world’s population, such as numerous communities in Asia and those who still build and live in vernacular buildings, there is hardly any application of and compliance with such codes. In one of my studies in the Solomon Islands,8 it was found that the local building codes simply did not acknowledge informal ways of building, and hence, it was proposed to review and update the codes with greater sensitivity to the local context. At this point in time, a synthesis between vernacular and modern knowledge is required, where both can inform the other.

Sustainable development and disaster resilience are closely linked; many of the targets and indicators of the UN’s Sustainable Development Goals (SDGs) are concerned with disaster risk reduction of the built environment as a way toward a sustainable future. A study by Sabater et al. mapped vernacular architecture to the SDGs;9 however, there are hardly any studies that specifically explore this link in the context of flood adaptive vernacular architecture. There is definitely an opportunity here to further examine within the transforming global context how vernacular architecture in flood-prone areas of South and Southeast Asia offers potential for developing the future’s resilient buildings. As climate change causes a wider range of challenges, lessons from this architecture will be key to dealing with future risks.

For more information see:
HABITAT: Vernacular Architecture for a Changing Climate, edited by Sandra Piesik and published by Thames & Hudson, USA, May 2024

References

  1. Ahmed, I. (2017). Flood adaptations in the Asian vernacular. In Piesik, S. (Ed.). Habitat: Vernacular architecture for a changing planet (pp. 508-513). London: Thames & Hudson.
  2. Steffen, W., Broadgate, W., Deutsch, L., Gaffney, O., & Ludwig, C. (2015). The trajectory of the Anthropocene: The Great Acceleration. The Anthropocene Review, 2(1), 81-98.
  3. Ahmed, I., Pal, I., & Chonlasin, V. (2023a). Complexities of post-disaster recovery: An example from Thailand. Asian Currents, 8 November 2023.
  4. Watts, J. (2024). Global heating and urbanisation to blame for severity of UAE floods, study finds. Retrieved on 4 May 2020 from https://www.theguardian.com/world/2024/apr/25/global-heating-and-urbanisation-to-blame-for-severity-of-uae-floods-study-finds
  5. Ahmed, I., & Parrack, C. (2022). Shelter self-recovery: The experience of Vanuatu. Architecture, 2(2), 434-445.
  6.  Ahmed, I. (1998). Crisis of natural building materials and institutional intervention. Habitat International, 22(4), 355-374.
  7.  Siossian, E. (2022). Lismore’s floods see families cling to floating furniture in bid to save themselves. Retrieved on 4 May 2020 from https://www.abc.net.au/news/2022-02-28/lismore-floods-see-families-cling-to-floating-furniture/100867228
  8. Ahmed, I. (2023b). Addressing the impacts of inland floods on informal housing in Honiara, Solomon Islands. In Dahiya, B., Pascale, F.D., Pietro, O.D., Farabollini, P., Lugeri, F.R., & Mercatanti, L. (Eds.). Disaster resilience and human settlements: Emerging perspectives in the Anthropocene (pp. 61-81). Singapore: Springer Nature.
  9. Sabater, A.L., Andújar, V.G.L., & Laumain, X. (2022). The SDGs as a useful tool in vernacular architecture management: The case of “17 objectives and a map”. Proceedings of HERITAGE 2022 – International Conference on Vernacular Heritage: Culture, People and Sustainability (pp. 671-678), Valencia, Spain.