High-rise living – sustainable or not?
10 May 2013
By Lynne Blundell
15 February 2011 – FAVOURITES [Ranks second most visited article of all time, after Sekisui House: green wave rolling out in the land of Oz] A visit to Hong Kong and China inevitably leads to thoughts of urban planning and the realities of high density living. Lynne Blundell returned from such a trip and has looked at research that challenges the current high-rise approach to sustainable cities. It reveals that not only the designs of tall buildings must improve but regulatory change to fast-track product innovation and sustainable refits is long overdue.
Hong Kong and the mega-cities of China open one’s mind to the realities of vertical living. In Hong Kong and Macau, two of the most densely populated places on the planet, vast expanses of towers reach like elongated fingers into the clouds, or more often pollution haze. Vertigo is a liability in these places. In Shanghai the statistics are hard to get your head around – 19.21 million people, very nearly the population of Australia, in one city. It gets you thinking about the future of cities.
And as urbanisation rates explode around the globe, governments and urban planners increasingly see more high-rise as the answer to reducing urban sprawl and creating more sustainable cities. Australia is no exception with both federal and state government policy targeting high density development, particularly along transport nodes.
But questions are being raised about the sustainability of this approach – questions about the amount of energy used by tall buildings and the energy embodied in their materials through to the social impacts of living and working in them. If high-rise is the way we are heading we need to do it much better say researchers.
Green Building Council of Australia and World Green Building Council chair, Tony Arnel, challenged the high density vision for our cities when he told the G’Day Conference in the US recently that high-rise buildings were not more sustainable than the suburban home.
Arnel, who is also Victorian Building Commissioner, quoted an Allen Consulting report done for the Victorian Building Commission that has found there is “no conclusive evidence that vertical living was more sustainable than conventional homes.”
The study, says Arnel, suggests buildings above three storeys begin to use more energy due to the need for lighting in common areas, lifts, security and the lifestyle of residents.
Certainly this is backed up by our earlier story where we reported that a NSW Energy Australia study found a high-rise apartment uses 30 per cent more power than a typical detached house, much of it in common areas such as foyers and car parks. On the question of water use, Sydney Water statistics show multi-unit dwellings account for 14.3 per cent of Sydney Water’s consumption compared to 45.7 for single dwellings
A recent energy and water audit by Willoughby Council of the common areas in 25 Sydney multi-unit buildings showed that high-rise buildings generated four times as much CO2 as villas/townhouses and three times as much as low and medium-rise buildings. The council undertook the audits as part of its ClimateClever Apartments program and the buildings included townhouses and low, medium and high-rise apartment buildings.
The overall use and intensity of use of both power and water was much greater in high-rise than the other three categories. Willoughby Council concluded this was potentially due to “the additional centralised plant and equipment that often occur in high-rise buildings, such as swimming pools, spas, saunas, cooling towers, pumps and lifts.”
“The high energy usage may also be attributed to the arrangement of central hallways and underground carparks in high-rise buildings which generally have no natural light and must be lit and ventilated at all times to ensure safety and amenity for the large numbers of occupants.”
Embedded energy is another issue. A decade ago researchers at the School of Architecture, Deakin University, and the School of Architecture, University of Tasmania, found that high-rise buildings had 60 per cent more energy embodied per unit GFA in their materials than the low to medium-rise buildings. While the figure has improved due to improved manufacturing processes, embedded energy is still greater in tall buildings because of the higher load requirements.
The social implications of getting high-rise right are also profound. A study last year on high density living by the City Futures Research Centre in Sydney found that living in close physical proximity to neighbours and sharing facilities has a profound effect on residents of high density buildings.
The study, Living well in greater density, found that where relations with neighbours were good and buildings were well-designed and constructed the experience could have positive influences on both the physical and mental health of residents. Conversely, poor social relations and poorly designed and constructed buildings can have devastating effects:
“For example, where social relations are poor, residents can experience isolation, stress, concerns regarding safety (either as a result of concerns about other residents, or due to a lack of passive surveillance), and disruptions to the quiet enjoyment of the homes. Where the design and/or construction quality of the dwelling is poor, residents can experience health problems (for example due to unsatisfactory ventilation or insufficient outdoor space), lack of privacy, interrupted sleep (for example due to noise), and financial burdens (for example as a result of increased electrical costs for heating and/or cooling).”
The report pointed out that those who rent apartments (65.2 per cent of NSW apartments or units are rented according to data from the NSW Land and Property Management Authority) have the added issue of being powerless to change their environment – in NSW tenants don’t have a right to sit on the owners corporation where decisions about changes to common areas are made.
The report concluded that the key to successful high density living was ensuring properties were well constructed, designed and managed to encourage positive social relations.
Urban sprawl is no alternative
Deo Prasad, director of the Centre for Sustainable Built Environments, told The Fifth Estate, that while there are considerable challenges in creating more sustainable high-rise, both residential and commercial, urban sprawl was far less sustainable.
“Even with the energy downsides of high-rise, urban sprawl is a far worse option. Transport problems alone have enormous social and health effects. People who travel long distances to work spend less time with their families and their health is impacted. Then there are increased emissions and health costs associated with urban air quality,” says Prasad.
And more sustainable high-rise is definitely achievable, says Prasad. On-site energy generation via solar and wind technologies are advancing and work being done at the Centre for Sustainable Built Environments in collaboration with industry will enable renewable technologies to be integrated into roofs and facades in the near future.
Good passive design which reduces the need for airconditioning in apartment blocks is also making a big difference to energy use. And major progress is being made on reducing embedded energy in building materials.
The Centre for Sustainable Materials Research and Technology (SMaRT@UNSW) is currently looking at steel production and how much embedded energy can be reduced through increased use of recycled materials, says Prasad.
“Manufacturers are improving their processes by, for example, increasing the proportion they get from alternative energy sources. This reduces the embedded energy of materials.”
The sticking point for all of this is a lack of clear government policy. Renewable energy tariff schemes come and go and energy companies and manufacturers are left high and dry.
“Product innovation is lacking largely because of policy uncertainty. The types of products we are working on would be equally suitable for retrofits as for new buildings but we won’t have real progress until government shows some commitment to long term policy,” says Prasad.
“You can’t blame energy companies or manufacturers for not taking action – they need some certainty. By 2013 electricity is going to cost more than 30 cents per kilowatt hour compared to 20 cents now. If government would bring in policy to push research and development and at the same time engage the community we could get the building stock right and make some real progress.”
An overhaul of strata regulations needed
A major obstacle to sustainable upgrades in existing high-rise buildings is the current strata model in Australia. Strata law, which in NSW requires at least 75 per cent consensus of owners to make changes in common areas of apartment blocks, such as installing more efficient hot water systems, rainwater tanks, green roof or solar panels, effectively hampers streamlined decision making.
In addition, government incentive schemes at both federal and state level continue to classify owners corporations of apartment blocks as companies, locking the residents out of normal residential incentive schemes and forcing them to pay more for everything from finance to taxes.
But there is a push for this to change. Christine Byrne of the Green Strata Network told The Fifth Estate this week that she believed 2011 will be a year of major progress for the greening of apartment blocks.
“Momentum is building and I think this going to be a really big year,” says Byrne. “There is a growing awareness amongst [apartment] owners about what we need to do to be more sustainable and local councils have a genuine desire to bring about change.”
In Sydney a number of councils have introduced green apartment programs offering grants and education resources to apartment dwellers. Willoughby and North Sydney Councils both have programs in place and City of Sydney’s Green Apartment program is due to be launched this year. Meanwhile the council runs seminars and provides funding for the Green Strata Wiki (http://www.greenstrata.com.au/).
Finance has been another impediment to doing sustainable upgrades on apartment blocks, says Byrne.
“It is difficult to raise money under strata – it either has to be done through levies or through borrowing. As we can’t use common property as security when borrowing, finance is very expensive,” says Byrne.
This may change in NSW with the introduction of new legislation that will improve access to finance for sustainable upgrades for existing buildings by facilitating voluntary environmental upgrade agreements to be struck between building owners, finance institutions and councils.
The Local Government Amendment (Environmental Upgrade Agreements) Bill 2010 was passed by NSW Parliament late last year. In announcing the change, NSW Minister for Climate Change and the Environment Frank Sartor, said the Bill overcame two key barriers to retrofitting large commercial buildings and large strata unit blocks:
- Access to low-cost loan funds- at present, loans are made to companies that own buildings. This Bill enables the environmental upgrade loan to be directly attached to the property, to be repaid via an agreed extra council rate. This means loans can be secured more readily and at a lower interest rate.
- Split incentives – at present a landlord cannot pass through the cost of energy savings measures that directly benefit tenants via lower energy bills. As the loan repayment will be via a council rate charge, the portion of the project cost that will benefit the tenant can be passed through. The Bill includes a provision to ensure that no tenant would pay more as a result of the agreement, unless specifically agreed.
“It will encourage landlords to invest in energy savings upgrades because over time the resulting savings in electricity pay for the cost of the upgrades.
“Tenants will benefit over time from reduced electricity bills from energy efficiency upgrades that otherwise would have been unlikely to happen.”
Sartor said the finance sector has estimated that at least $2 billion worth of energy efficiency upgrades in the Sydney market could be unlocked as a result of this legislation.
Individual meters a must
A key factor in achieving zero carbon in developments is the use of decentralised energy and water solutions. This involves district and/or on-site power generation and water treatment. These solutions are rarely possible in apartment blocks because of common metering for both water and power.
Researchers at Griffith University studying the potential of decentralised water management systems in high density developments for the National Water Commission, found water savings were not possible without individual water meters as there was no incentive for individuals to change water usage without metering.
In addition those who occupied the units should pay the charge, the researchers said.
The need for individual lot water metering has so far only been recognised in Queensland where mandatory provisions were introduced for all lots in all new strata and community title developments approved after 1 January 2008 (all lots in class 2 to 8 buildings are to be fitted with individual water meters).
Queensland is also ahead when it comes to removing body corporate by- laws that discourage environmental upgrades. Since January 1 2010, new and some existing covenants and body corporate by-laws can no longer ban energy efficient features or fixtures, such as windows, roofing or solar hot water systems and panels, or require certain design elements that discourage sustainability.
Christine Byrne believes if the bureaucratic overlay regarding strata could be reduced around the country change would be swift.
“There are huge opportunities out there for people to create businesses to work with apartment owners, whether it is by providing services to councils to do audits or just to help increase knowledge and awareness,” Byrne says.