High-Rise Buildings that are Most Affected by Climate Change

Tower blocks can be considered the most vulnerable building type to climate change due to their exposure to the elements and their unfavourable volume-to-surface ratio (Bahaj et al. 2008). In tall buildings, where countless people are dependent on machinery for their very survival, hence consuming more and more energy, to compensate for the climate change. In February 1998 in Auckland, New Zealand, all four main cables into the central city failed, cutting electricity to offices and more than 5000 apartments. Backup cables also failed, due in part to the extreme summer temperatures 38 °C and for up to 8 weeks there was chaos in the city buildings, where temperatures soared to over 50 °C and allegedly in the top floors of tall buildings to over 80 °C, making their habitation impossible. Buildings with extremely high energy costs and exposure to extreme winds and solar gain may be one of the evolutionary types of buildings that die out first as the climate changes and the cost of energy rises over the next decades (Yeang 1999).

Traditionally, building design has relied to a considerable extent on historic climate data accumulated over time to provide design criteria for everything in buildings including structural systems, cladding and windows, site drainage, and HVAC systems. With the manifestation of climate change, this approach is also changing experts believe that historic data may no longer best represent future environmental conditions over the service life of buildings.

According to Shankha P. Bhattacharya and Sonam Singh, energy generation in high-rise buildings has been summarised (Bhattacharya and Singh 2013). Historically, the development of high-rise buildings can be clustered into five energy generations. These five generations are separated by each other with a connecting event. Four such connecting events are recognised as (1) introduction of 1916 New York zoning law; (2) innovation and use of curtain walls as building facade, 1951; and (3) the energy crises in 1970s; and (4) Rise of an environmental consciousness in 1997 (Oldfield et al. 2009). This study concludes that climatic change and global warming have presently become a burning issue worldwide. The requirement of environmental sustainability and further reduction in primary energy demand in buildings was noticed in late twentieth-century buildings. The sustainability index is measured for some selected energy conservation technology and design principles, and the analysis finally reveals that the traditional solar passive design principles with a building surface solar and wind energy generation technology could be the appropriate solution at present. Using recycled and industrial byproduct materials with rain water capturing systems will enhance the overall sustainability of the Indian tall building, but nevertheless this is limited to the Indian context (Oldfield et al. 2009).

A recent book by Stefan Nijhuis and edited by Han Meyer and Daan Zandbelt (2013) has addressed many questions on high-rise buildings and the sustainable city; among these questions are: Can high-rises make a fruitful contribution to making cities more sustainable? Many argue that high-rises deliver positive environmental effects, such as densification, and reduction of traffic and carbon dioxide emissions. Questions such as the impact of tall buildings on the environment; their ideal densities; successful design features in a tall building; reputations of high-rise buildings and their expectations; their sustainability, reuse, and reduction of negative environmental impact were discussed. The study also tackled the meaning of high-rise buildings for a sustainable city and asks when urban form can be considered as “sustainable”. The second part focuses on transformation and area development and the processes necessary to densify the city and to develop high-rise buildings. The main question here is if it is possible to develop high-rise projects that energise city life. It was concluded that discussing the design features of the buildings themselves as sustainable structures will contribute to a healthy indoor and outdoor environment and to a reduction of materials, energy, and costs (Nijhuis 2013). All these points are very crucial in considering the development of tall buildings and climate change impacts.

High-rise buildings with glass fafades in Abu Dhabi and Dubai, UAE. Photos credit

Fig. 9.28 High-rise buildings with glass fafades in Abu Dhabi and Dubai, UAE. Photos credit: Author

Over the next 40 years, if buildings do experience increases in environmental loads (temperature, relative humidity, rainfall, snowfall, wind pressures, and UV radiation), in addition to changing the design criteria, these changes could have a significant impact on buildings stock (Lotfabadi 2015). Obviously, these issues are of interest to design professionals and policy makers. As skyscrapers are consuming a great deal of energy and are indispensable in modern cities, considering new ways of benefiting from renewable energies can have a vital role in reducing buildings’ energy consumption (Lotfabadi 2015). This would assist in the adaptation measures to encounter climate change risks.

One of the most crucial elements in energy consumption in tall buildings development is the envelope, mainly the glass used in enormous skyscrapers around the world, for example the UAE as shown in Fig. 9.28. Glazing, a major feature in reducing energy use that also offsets the impact of climate change is carefully examined and properly selected in tall buildings. Glazing may lessen GHG emissions, mainly CO2 and offset climate change risks. A study was conducted in the UAE on a typical 30-storey residential building with a WWR of 50 % and a north-south orientation focussing on the decision of selecting a glass type for a high-rise building to assess the significant impact on the initial and running cost of the building. The glass types (b, c, d, e, g, f, g, h, i) were classified in terms of SHGC and U-value from 0.25 to 0.14 and 2.00 to 1.10 W/m2 K, respectively (Tibia and Mokhtar 2014). It focused on several competing factors which influenced the architect’s decision to focus on the relationship between the glass thermal characteristics and its cost using an energy simulation modelling tool to provide data on the impact of different types of glass on the cooling load, and hence the energy consumption. The simulation relies on both the simple payback period and the life cycle cost (LCC) reduction techniques, optimal glass thermal properties. Results indicated that glass type g (SHGC of 0.20 and U-value of 1.30 W/m2 K) shown in Box 9.2 has one of the shortest payback periods and the lowest LCC in Abu Dhabi, Dubai, and Sharjah (the three largest emirates in the UAE). The study also recommended the use of this glass type for high-rise residential buildings with about a WWR of 50 % and with an almost north-south orientation in a hot-humid climate (Tibia and Mokhtar

Box 9.2 Minimum glass thermal characteristics when the WWR = 50 % (Tibia and Mokhtar 2014)

Abu Dhabi

Dubai

Sharjah

• U-value = 1.9 W/m2 K

• U-value = 1.9 W/m2 K

• U-value = 2.1 W/m2 K

• SHGC = 0.23 (Using

prescriptive pathway values of Estidama)

• SHGC = 0.28

• SHGC = 0.30

• This is roughly glass type E

• This is roughly glass type C

• This is roughly glass type B

2014). It is worth noting that the currently used codes in these emirates require the following minimum glass thermal characteristics when the WWR = 50 % (Tibia and Mokhtar 2014).

 
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