RobxWox

24/01/2022

Making cities cooler is a no brainer – so why are we doing so little about it?
You walk through a park in a city on a warm day, then cross out to a narrow street lined with tall buildings. Suddenly, it feels much hotter. Many people will have experienced this, and climate scientists have a name for it: the urban heat island effect.

Heavily urbanised areas within cities are between 1℃ and 3℃ hotter than other areas. They are contributing to global warming and damaging people’s health, and it’s set to get worse as urbanisation intensifies.

Numerous cities around the world are trying to do something about this problem. But there is a very long way to go. So what is holding us back, and what needs to happen?

Urban heat relates to how most cities have been designed. Many rows of tall buildings are organised into blocks which resist any natural breeze. Streets and roofs are clad in dark materials like asphalt and bitumen, which retain more heat than lighter materials and natural surfaces like soil.

Roll out the bitumen. Dmitry Kalinovsky
Natural ground absorbs rain, which is evaporated by the sun’s rays on a warm day and released into the air, cooling everything down. In a city, the rain just runs into the sewer system instead.

Urban areas tend to lack trees. Trees help reduce the air temperature by blocking the sun’s rays, while cutting the levels of pollution by absorbing harmful particles.

Cities are also warmer because they are full of human activity. Everything from transport to industry to energy output makes them hotter than they otherwise would be.

Cause and effect
Urban heat has various consequences. Combined with heatwaves and global warming, both of which are also on the rise, these hotspots are producing conditions that kill and hospitalise growing numbers of people. The worst affected are the elderly and other vulnerable groups like the homeless.

The World Health Organisation (WHO) has warned that increased city temperatures lead to more pollutants in the air. These can aggravate respiratory diseases, particularly among children. As cities get bigger, more and more people will be affected by these threats to their health.

Il fait chaud. VladisChem
Higher city temperatures are one reason why we are using more and more air conditioning. One US study found that the urban heat island effect in Florida was responsible for over $400m (£287m) of extra aircon, for example.

Aircon feeds climate change by producing more carbon emissions through the extra electricity demand, creating a vicious circle where it gets hotter because more aircon is required. The increased energy demand means a greater risk of summer blackouts, causing both human discomfort and economic damage.

Hotter city roads and pavements also raise the temperature of storm-water runoff in sewers. This in turn makes rivers and lakes warmer, which can affect fish and other aquatic species in relation to things like feeding and reproduction.

Finally, there are major economic consequences to hotter cities. One paper from last year predicts that all the extra wear and tear caused by the excess heat would amount to between 1% and 10% of lost GDP in thousands of cities around the world.

How we’re reacting
The solutions to the problem are clear enough: they include using paler more reflective building materials, and wiser urban planning that incentivises more parks, tree planting and other natural open spaces.

When it comes to taking these steps, however, it’s a very mixed picture. Countries and municipal authorities have typically become very good at adopting plans to cut emissions of carbon dioxide and other greenhouse gases. They are not so good at taking steps to adapt to climate change. A study from 2014 found that most European cities had failed to introduce urban heat plans, and the situation looks little better today.

This being the case, city administrations that have gone the extra mile look particularly enlightened – even though they tend to be somewhat sporadic. Melbourne, for instance, has substituted its trademark bluestone pavements in several areas with a permeable version that absorbs rainwater, thereby increasing the amount of evaporation.

New York City’s Cool Roof Initiative has seen thousands of volunteers painting some of the city’s flat bituminous roofs with a reflective polymer material. Lately, Los Angeles has launched an initiative to paint roads white, part of a pledge by city hall to lower the temperature by 3℃ in the next 20 years. Beijing, meanwhile, has been introducing zoning measures to reduce smog.

Other administrations have been encouraging green roofs – rooftops covered in vegetation: they are a legal requirement for big new developments in Toronto; there are floor area bonuses for developers who include them in Portland, Oregon; and Chicago had a funding scheme for a while. In Swiss cities and regions, green roofs have been a legal requirement for many buildings for years.

Lofty shoots. Alison Hancock
These are all just pockets of activity, however. Many other mayors and city administrations need to start implementing the kinds of bylaws and incentives to adapt to the reality of hotter cities.

The cities of the future can still be green and cool, but only if they move up the agendas of many city halls. The laggards need to follow the example of those that have been leading the way. The reality is that the social, environmental and economic costs of urban heat islands add up to a bill that is too high for humanity to pay.

24/01/2022

Making every building count in meeting Australia’s emission targets
Buildings in Australia account for over 50% of electricity use and almost a quarter of our carbon emissions but the failures, frailties and fragmentation of the construction sector have created a major obstacle to long-term reductions. Reducing our carbon footprint plays second fiddle to the multibillion-dollar work of replacing flammable cladding, asbestos and other non-compliant materials and ensuring buildings are structurally sound and can be safely occupied.

Buildings – whether residential, commercial or institutional – do not score well under the nation’s main emissions reduction program, the A$3.5 billion Climate Solutions Package. This is intended to help meet Australia’s 2030 Paris Agreement commitment to cut emissions by 26–28% from 2005 levels.

This climate fund has very successfully generated offsets under the vegetation and waste methods – these projects account for 97% of Australian carbon credit units issued. But built environment abatements have been very disappointing.

Read more: Buildings produce 25% of Australia's emissions. What will it take to make them 'green' – and who'll pay?

Australians have very high emissions per person. That’s partly due to how we use our buildings.

Our states and territories control building regulations. This year the Council of Australian Governments (COAG) set ambitious energy-reduction trajectories for buildings out to 2022 and beyond. This was to be achieved through amendments to national codes and implementing energy-efficiency programs.

Making the best use of our buildings
Last month, the Green Building Council and Property Council launched a policy toolkit, called Making Every Building Count. The councils urged governments to adopt practical plans to reduce emissions in the building sector.

The toolkit contains no fewer than 75 recommendations for all tiers of government. These are the result of work done through industry and university research partnerships in places like the Low Carbon Living Collaborative Research Centre – now disbanded after its seven-year funding ended.

Read more: We have the blueprint for liveable, low-carbon cities. We just need to use it

Most energy-efficiency studies and programs focus solely on the operational aspect of buildings, such as the energy used to heat and cool them. However, various studies have proved that the energy and emissions required to manufacture building products, even energy-saving products such as insulation, can be just as significant.

A more holistic approach is to look at the embodied energy already in our building stock, which then poses a serious question about our consumption. So, besides aspirational codes for net zero-energy buildings, we should be asking: can we meet our needs with fewer new buildings?

Read more: The other 99%: retrofitting is the key to putting more Australians into eco-homes

In Melbourne, for example, an estimated 60,000 homes are sitting unused. Commercial property has very high vacancy rates – up to one in six premises are unoccupied in parts of the city. This points to a less-than-effective market in valuing our embodied carbon emissions in property.

If we are to get serious about reducing emissions, we need to tackle inefficient space use.

Empowering people to cut emissions
In occupied commercial buildings, some evidence suggests most building managers are grappling with complexity and challenging tenant behaviours. They also don’t get the clear information they need to continually improve their building’s performance beyond a selected benchmark.

In residential property, home energy performance is very much in our own hands. So we need to consider the means, motivations and opportunities of households, which I did in my doctoral study. A major barrier is that most of us don’t even know what we are getting when we buy or rent an ageing stock of more than 9 million homes.

Europe and the United States moved to mandatory residential energy disclosure at point of sale and lease well over a decade ago. If you rent or buy a home in these countries you get an energy performance certificate. It identifies emissions intensity and gives advice on how to operate the home more efficiently and hence with lower emissions.

In Australia, we have just sat on a commitment made by COAG back in 2009 to introduce a nationwide scheme.

Size matters, too. Residential space per person is high by international standards. Although McMansions are on the wane, our apartments are getting a bit bigger. The average size of freestanding houses built in 2018-19 shrank by 1.3% from 2017-18 to a 17-year low of 228.8 square metres.

And we are putting more solar on our roofs as a carbon offset. As of September 30 2019, Australia had more than 2.2 million solar photovoltaic (PV) installations. Their combined capacity was over 13.9 gigawatts.

However, the trend towards high-rise living is not helpful for emissions. Solar for strata apartments is tricky.

The trend towards apartment housing in Australian cities makes it harder for residents to use solar power. Darren England/AAP
I recently worked with colleagues in Australia and overseas in a study of the user experience of PV. We found residents face a range of issues that limit emission reductions. These issues include:

initial sizing and commissioning with component failures such as faulty inverters
lack of knowledge about solar and expected generation performance
regulatory barriers that limit the opportunity to upgrade system size.
Looking to improve regulations and codes and billion-dollar funds may be sensible ways to meet emission targets, but human empowerment is the secret weapon in improving energy performance and lowering emissions. Good low-carbon citizens will help create good low-carbon cities.

Read more: Cutting cities' emissions does have economic benefits – and these ultimately outweigh the costs

A set of clear guides on how to use a building is a good starting point. The low-carbon living knowledge hub provides these.

What will make every building count in lowering emissions is the behaviour of occupants, the commitment of owners to make their buildings low-carbon and building managers’ ability to become more adept at reducing building-related emissions.

24/01/2022

How Chinese courtyard housing can help older Australian women avoid homelessness
Australia urgently needs housing types that meet the needs of older women facing homelessness. One such model is Chinese siheyuan courtyard housing, which provides safe, affordable and private living spaces while maintaining a sense of community. It has potential for adapting existing buildings for re-use in Australia in a way that makes financial, social and environmental sense.

Women over 45 are one of the fastest-growing groups of people who are homeless in Australia. In 2020, an estimated 405,000 women over 45 were at risk of housing affordability stress and hence becoming homeless. Considering the shortage of affordable housing, an ageing population and the lifelong economic disadvantage that women experience, this problem requires a speedy solution.

Read more: 400,000 women over 45 are at risk of homelessness in Australia

A simple (and obvious) solution for older women facing homelessness is to provide them with access to appropriate, safe and affordable homes for the long term. So why is this problem so difficult to solve?

Recent attempts to meet this need for older women’s housing include “pop-up” or “meanwhile use” accommodation in vacant aged-care facilities and tiny houses. While both types provide good short-term options, they do not create long-term housing that meets older women’s needs to age in place and have secure tenure and a sense of belonging. All these aspects are important for their well-being.

Read more: 'Meanwhile' building use: another way to manage properties left vacant by the COVID-19 crisis

What if we were to take the idea of adapting existing buildings and merge it with the idea of tiny homes? Chinese courtyard housing – siheyuan – has some important principles that could be culturally adapted to the Australian context.

Finding new spaces in old stock
Adaptive reuse involves the conversion of new spaces within old ones. An existing building is recycled by integrating a new set of functions into the existing skin to suit the needs of new inhabitants.

This is not a new concept – think of the Hagia Sophia in Istanbul, variously a church, mosque and museum. Or Paddington Reservoir in Sydney, originally infrastructure, then petrol station, then ruin, now urban performance space.

Adaptive reuse works on a triple-bottom-line approach: economic, environmental and socio-cultural. Recycling an existing building is cheaper, better for the environment and ensures the collective memory of a place is not erased. For buildings as for older women, respect for age, connection to place and care for the environment are important.

Read more: Unused buildings will make good housing in the world of COVID-19

Chinese wisdom in an Australian context
The name “siheyuan” translates into quadrangle courtyard housing. This type of housing comes from traditional Confucian ideas of the extended family unit, arranged around a courtyard or series of courtyards with graduated levels of privacy.

Hugo Chan, Author provided
The interesting thing about the siheyuan arrangement is the highly ordered series of rooms with private units organised around open spaces and communal halls for gatherings. In Beijing today, an estimated 400,000 courtyard houses remain. About 500 have been preserved as historic sites.

The hierarchical order of the siheyuan presents a great opportunity for adapting it to suit the needs of older women. It’s a type of co-housing arrangement: people live independently but together, sharing some facilities like open space and areas to come together for occasional meals. This model could form part of the rise in shared housing configurations.

Read more: Co-housing works well for older people, once they get past the image problem

The courtyards meet the needs of older women to maintain a strong connection to a garden space, with potential for them to be active in maintaining this area. The courtyards promote social contact and exercise, as well as space for quiet contemplation. This interior-landscape connection is important to the well-being of older women.

tradition Chinese siheyuan courtyard housing
The connections between private living areas, courtyards and gardens promote well-being through social contact and exercise. ByLorena/Flickr, CC BY-NC-SA
The hall serves as a social connector. It’s a place for communal activities, connecting with family or friends, creative projects or listening. Women retain their sense of independence; they decide when they participate.

Another important requirement for older women is to have the space to welcome family and friends, so they maintain their social connections to the world. The hall is an efficient way to share space that everyone needs, but only some of the time.

The private units ensure the independence, safety and sense of belonging that older women need. Cultural and social needs are met easily within one’s personal domain.

The small luxury of having a room of one’s own should not be underestimated. Many older women have rarely had this luxury. For them, it provides much-needed dignity.

Read more: What do single, older women want? Their 'own little space' (and garden) to call home, for a start

The adaptation mindset
This sort of adaptive reuse is not just about what we do with existing buildings. It’s also about adapting cultural wisdom, and ideas from the past, to develop alternative ways of living together. Many currently underutilised or vacant buildings in Australia could be adapted to courtyard housing.

It will need a radical shift in policy and developer-driven economics. But this opportunity would meet so many current needs of older women, be good environmental practice and provide social housing. As Confucius said, “Everything has beauty, but not everyone sees it.”

The financial burden on taxpayers and service providers is dramatically reduced by providing secure affordable housing in the first place. The solution to the problem of homelessness lies not in our obsession with new housing models or new development, but perhaps, if we look hard enough, in our existing urban fabric. Right under our noses, existing buildings offer opportunities ripe for adaptation.

24/01/2022

24/01/2022