Ilan Vizel from the University of New South Wales recently presented a paper at the State of Australian Cities conference. His paper studies the knock down and rebuild phenomena of older detached houses that were previously inhabited by older owner-occupiers.
A&D spoke to Vizel about the research and how it will inform the architecture and building industry.
Can you tell A&D about your research?
Our study explores the drivers and impacts of ‘knockdown and rebuild’ activity in Sydney — the demolition of older houses and their replacement with new ones. This activity is happening right across Sydney and is especially prominent in some of Sydney’s postwar suburbs, where you can now drive along and observe a mix of older single-storey fibro and brick houses built in the 1950s and 1960s alongside modern and larger project homes.
One of the aspects we are examining is whether the observed physical change to suburban streetscapes is also associated with social and demographic change. One of the demographic aspects we examine is the role of different generations within these housing market dynamics. The study is based on our analysis of over 6,800 development applications for knockdown and rebuild since 2004.
How do different generations approach housing differently?
Those who were born in the two decades before World War Two, sometimes referred to as the ‘Austerity Generation’, would typically stay most of their adult life in the same house, more often than not as owner-occupiers in detached suburban houses.
However, from today’s perspective, their housing aspirations were relatively modest: smaller houses compared to those built today, often just two- or three-bedrooms, one bathroom and one living space.
The Baby-Boomers experienced higher rates of residential mobility. But generally speaking, most Baby Boomers continued to enjoy high levels of homeownership and, predominantly, a continuing preference for low-density suburban living.
Those described as Generation X are more divided in terms of their housing experiences. There is a large group of Gen-Xers who cannot afford to enter homeownership. Housing affordability in the private rental market is becoming a real issue for many Gen-Xers.
At the same time, within the larger cohort of Gen-X, there is a sub-group of affluent households who already own a house or a flat and are now in a position to upgrade as second or third time buyers. Quite a number of these people, often young families, do not wish to move to the outer-metropolitan fringe when they can afford to buy a property in a more convenient middle-ring suburban location.
So they buy an old 1950s brick or fibro house, often from an older ‘austerity generation’ couple, and through ‘knockdown and rebuild’ they replace it with a new house that fits their expectations: two-storey, four-bedroom houses with two to three bathrooms and two to three living spaces. They are willing to trade-off a smaller backyard for the sake of a larger house.
It is probably too early to talk about the housing careers of Generation Y and those that follow.
How do you expect this to change over time?
It is always hard to guess what lies ahead, but housing expectations have changed since the 1950s so it is likely that more and more of the older housing stock in the postwar suburbs will gradually be replaced with newer stock. But there are various pressures and dynamics that will influence what sort of new housing will be built.
In areas that will be zoned for higher-density development, one-to-one replacement of detached dwellings as we observed in our study is not likely to continue to the same extent, and we’ll see more medium density housing offering higher yields for investors and greater housing opportunities for the larger cohort of Gen-Xers and younger generations.
What were the outcomes of the research?
So far, we’ve found that Gen-X led households play a key role in driving knockdown and rebuild activity in Sydney. They are, by far, the majority in our sample of 1,200 households. We also found evidence that many of them replaced older residents who lived in the houses that were later demolished through the knockdown and rebuild process.
This social change in suburbs with significant knockdown and rebuild activity is more subtle but just as important to suburban character. We also detect that relatively affluent second and third generation migrants are active participants in the knock down rebuild phenomenon in some suburbs for both economic and family-tie reasons.
How do you hope the research will change and inform the architectural and building industries?
Knockdown-and-rebuild is a market driven phenomenon which is enabling many households to upgrade — and upscale — their living standards within established suburbs. However, there are some concerns attached.
The process involves the loss of lower-value older housing stock and its replacement with larger and more expensive housing. This may have negative impact on housing affordability in Sydney.
There are also environmental concerns. New houses must conform to environmental standards that are higher than those they replace. Yet our study demonstrates that most of the new houses built use a significantly larger proportion of the lot, often verging toward what the popular press might term McMansions and with potential negative environmental impact through the cumulative loss of green space.
There is a need for planning policies to ensure that the environmental costs of demolition and reconstruction are minimised through recycling and other energy-saving practices, as well as protection of private gardens through regulated site coverage.
Spot redevelopment of this kind can also fall short of the economic, environmental and social benefits that can come from a more integrated approach to suburban re-design.
Architects and builders need to be aware of these negative implications and offer designs and perhaps alternative solutions that balance the desire for large homes with broader community considerations.
