Opinion: It is a typical summer’s afternoon in Gujarat, India. Women and children are listless as they swelter in the 34C heat. It’s even hotter outside. Families that have moved into affordable housing units built in the last few years are finding their comfort and health have not been sufficiently considered in the design and construction of the new dwellings.
There are similar problems in Indonesia – where one study showed most household energy use was dedicated to trying unsuccessfully to stay cool – and Australia, where tenants in rental properties were regularly experiencing indoor temperatures above 30C in summer.
We are experiencing a ‘heat pandemic’. And it’s caused by lousy buildings. Homes could be refuges from the impacts of climate change, rather than silent contributors to the climate emergency. But for that to happen requires changing the way we build so homes are suited to future climates.
Cooling is a top priority when finances allow. But this demand for cooling is accelerating growth in demand for electricity, which is still predominantly generated with fossil fuels, thus increasing greenhouse gas emissions, and global warming
Heatwaves are the leading cause of climate-related deaths in Europe and the United States, and building design is a major contributing factor. A recent report by the European Commission calls for a sustainable cooling strategy that also takes into account the need for equitable access to thermally comfortable buildings.
Increasing average and extreme temperatures, urbanisation, accelerating cooling energy demand, and an ageing population are increasing the vulnerability of millions to heat-related health risks globally.
For most people in Gujarat supplementing the poor thermal performance of their homes with air-conditioning is unaffordable. Cooling is a top priority when finances allow. But this demand for cooling is accelerating growth in demand for electricity, which is still predominantly generated with fossil fuels, thus increasing greenhouse gas emissions, and global warming.
India has approved the construction of 8 million new affordable housing units over the next two years. If these buildings are not designed to enable people to stay cool and healthy without air-conditioning, then millions of people will become more vulnerable to the health and social impacts of climate change.
Simple low-cost design changes can make a big difference. For example, using more insulating wall materials, ensuring windows have appropriate shading, and providing ventilation louvres above doors and insect screens so windows can be opened without letting mosquitos in, can reduce annual cooling loads by about a quarter compared with standard practice, shows research by Monash University to be published soon.
A research collaboration between Monash and the Global Buildings Performance Network of energy use in Indian and Indonesian homes is showing this is not unique to India. As global warming progresses, people in already warm climates around the world are becoming increasingly vulnerable to overheating in their homes.
A study in the Indonesian city of Samarinda showed that most household energy use was dedicated to trying to stay cool. Yet, the poor design of houses led to average indoor temperature and humidity being about the same as outdoor conditions – above 27C and 70 percent humidity – even when air conditioner thermostats were set to 20C.
Lack of shading and natural ventilation coupled with poorly insulated and constructed walls and roofs means buildings heat up quickly and let cooled air leak out.
Despite some Australian state governments and municipalities declaring a ‘climate emergency’ and producing action plans to achieve net-zero emissions by 2030, these have had a limited impact on the climatic adequacy of new housing and renovations. Planning controls applicable to new townhouses, for example, are not able to be modified to ensure buildings provide thermal comfort and zero-net emissions without state government approval. Councils also seldom have influence over the performance of single dwelling proposals or renovations beyond enforcing the National Construction Code.
If climate change benefits don’t convince governments and industry, then the health and economic benefits might. Yet this is not a narrative framing the debate about policy reforms in the buildings sector.
Monash University and the Global Buildings Performance Network released a global evidence review during COP26 showing the benefits of implementing policy for zero-emissions buildings go beyond keeping global warming well below 2C.
A key finding was that sustainable building practices – those that reduce carbon emissions across all phases of the building cycle from design and material choice to supply chains and waste management – deliver substantial physical and mental health benefits. There is also evidence that up to a fifth of the value of energy savings from well designed and implemented energy efficiency building retrofitting and renovation policies relate to direct health benefits such as lower rates of respiratory illness and heart disease.
In the European Union, for example, direct health benefits of energy efficiency building renovation was estimated at €2.86 billion by 2020. Indirect benefits include better physical and mental health. Improving and safeguarding thermal comfort in homes is therefore a priority.
There were also significant job creation and economic benefits. Each US$1 million invested in Energy Efficient Buildings creates about 14 job-years of net employment with as much as 16 million jobs a year possible in the green building market globally. It also drives improvement in productivity of the construction value chain.
Policies such as mandating net-zero energy performance in building codes leads to a positive return on investment to public finances over time. For example, direct and co-benefits of energy efficiency measures have the potential to add 1 percent growth in GDP in Germany.
Higher energy efficiency performance also leads to lower home operating costs. Energy efficiency measures to eliminate fuel poverty in 2.5 million homes in the UK provided a net economic benefit of £1.2b in 2008. Other non-health benefits reported included cost savings to households, educational benefits of enhanced lighting and increased energy security.
As part of the review, the research team conducted interviews with policy influencers in Indonesia and India, and shot video of people at home to determine whether the lived experience of people living in more sustainable housing matched the evidence base. Householders talked about cost savings and the health benefits from moving into affordable sustainable housing in Jakarta Indonesia.
Which raises the question: if sustainable building delivers so many ‘win-wins’ why aren’t all new buildings sustainable? It turns out the health and other benefits of sustainable building which have been reported in research are either not well-known in practice, or not often used to promote sustainable building.
Because sustainable building has been viewed primarily through the lens of climate change, other sectors that could benefit such as health, transport, energy and real estate have not been effectively brought into the conversation. Doing so could help convince more people that sustainable building is the ultimate ‘win-win’.
Peter Graham is an Associate Professor in Architecture at Monash University, Australia and the Executive Director of the Global Buildings Performance Network, an international network of experts dedicated to achieving the mitigation of greenhouse gas emissions from the buildings sector.
Professor Peter Bragge specialises in evidence reviews to support better decision making for policy and practice. He is Director of Monash Sustainable Development Institute’s Evidence Review Service (ERS), which delivers research and practice reviews to a diverse range of government and industry organisations.
Kate McFarlane is a Research Manager in Architecture at Monash University, Australia and the Head of Networks and Engagement at the Global Buildings Performance Network.
This article has been updated and republished to reflect the record heatwave affecting most of the northern hemisphere. It was originally published on March 13, 2023.