Badly built housing propels the heat pandemic in Asia's cities

Australia Broadcast Center

06-06-2025

It is a typical summer's afternoon in Gujarat, India. Women and children are listless as they swelter in their homes in the 34-degree Celsius 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 issues 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 exacerbated by lousy buildings.
Tens of thousands of people were made ill during India's heatwave. ( AP: Manish Swarup )
Changing the way we build homes
For that to happen it requires changing the way we build, so homes are suited for future climates.
India recorded more than 40,000 suspected heat stroke cases and at least 110 confirmed deaths between March 1 and June 18 2024, when its north-western and eastern parts recorded more than twice the usual number of heatwave days.
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 by the end of 2025. 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.
India is building millions of new residential apartments across the country. ( AP: Amit Dave )
Simple, low-cost solutions
Simple low-cost design changes can make a big difference.
Using more insulating wall materials, ensuring windows have appropriate shading, providing ventilation louvres above doors and insect screens so windows can be opened without letting in mosquitoes, can reduce annual cooling loads by around 25 per cent compared to standard practice, research by Monash University and the Global Buildings Performance Network shows.
Research into energy use in Indian and Indonesian homes is showing that 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 per cent 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.
Demand for air coolers always rises when India is hit with heatwaves. ( AP: Amit Dave )
Changing the debate
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, the health and economic benefits might.
Yet this is not a narrative currently framing the debate about policy reforms in the buildings sector.
A global evidence review showed 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 one 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.
Researchers say sustainable building practices can deliver substantial physical and mental health benefits. ( ABC Central West: Hugh Hogan )
There are health benefits
In the European Union, direct health benefits of energy efficiency building renovation was estimated at 2.86 billion euros by 2020. Indirect benefits include better physical and mental health.
There were also significant job creation and economic benefits. Each $US1 million invested in energy efficient buildings creates about 14 job-years of net employment with as much as 16 million jobs per annum 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 per cent 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 1.2 billion British pounds 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.
Which begs the question: if sustainable building delivers so many 'win-wins' and could end our 'heat pandemic' 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 and Executive Director of the Global Buildings Performance Network.
Professor Peter Bragge is Director of Monash Sustainable Development Institute's Evidence Review Service.