Dark roofs will be banned on all new houses in New South Wales and large commercial buildings will need to meet net-zero carbon emission standards, the state’s planning minister has announced.
The government announced a ban on dark roofs in key development areas back in August but will now move to formalize the ban across the state.
In a speech to the Committee for Sydney, Rob Stokes cited University of NSW and University of Sydney research that shows that dark roofs could be lifting ambient urban temperatures by up to 2.4 degrees.
“There are no practical reasons why we shouldn’t be ditching dark roofing on new homes permanently to ensure that future communities of Sydney’s west don’t experience the urban heat that many communities do now,” he said, according to media reports.
“This would have an enormous impact on the urban heat island effect in our city, and I will be asking the Department of Planning to implement this as part of our ‘net zero cities’ approach.”
The kind of development seen in Sydney’s sprawling suburbs, particular in the city’s west and south-west, has long been criticized as inappropriate and unsustainable, with a lack of green infrastructure and dark-roofed houses built to the edge of blocks exacerbating the urban heat island effect.
Discussing the UNSW and University of Sydney research into building materials and urban temperatures, lead researcher Mattheos Santamouris noted that low-quality housing can have a marked influence on temperature and energy use.
“The temperature difference between Eastern and Western Sydney during summer, for example, is up to 10 degrees. In a distance of 60 kilometres, that’s tremendous,” he said.
“This has a tremendous impact on the quality of life of people in Western Sydney. They spend almost 100 percent more energy on cooling. They have much higher mortality rates.”
Committee for Sydney chief executive Gabriel Metcalf welcomed Stokes’s announcement of the ban, The Guardian reports.
“Of all the things that can be done about the problem of living with extreme heat in western Sydney, the easiest is requiring light coloured roofs,” he said. “This makes all the sense in the world.”
Stokes also said that the BASIX certification system which assesses the energy performance of housing will be updated, with the required rating lifted from 5.5 stars to 7 stars for new dwellings. Office towers, hotels and shopping centres, meanwhile, would be required to have their energy usage running at net-zero emissions from 2022.
Net zero targets for buildings are often criticized as they can exclude embodied carbon and rely on sometimes-dubious offsetting schemes.
Stokes said the proposed changes would have real effect. “Our proposed changes will save another 150,000 tonnes of carbon a year, helping achieve net zero by 2050,” he said.
Source: Architecture - architectureau
