Density - it's a dirty word in public commentary around development.
More people in smaller spaces - how does this concept gel with Canberra's expansive, open-spaced ethos?
But it's a concept that's been bandied around since Canberra's earliest days, and especially in the decades after the war. Canberra had plenty of open space, but wasn't ready to expand outwards from its initial borders.
And as the postwar population grew rapidly, the government had to make quick decisions on how best to fill the space.
Imagine, for a moment, that the ACT government had to decide what kind of dwelling was suitable for the average Canberra family.
What would be the requirements, and what style of house would it be?
Would the ideal family home have three bedrooms, or four? One bathroom or two? An open-plan living-dining room and back veranda? Space for two cars?
And would there be different levels of housing, depending on the occupations of the inhabitants? Would a public servant get a better house than a construction worker?
We can all thank our lucky stars that these decisions will never be left to government.
But in the years immediately following World War II, and for several decades thereafter, the Commonwealth government - ACT was not yet self-governed - played a crucial role in deciding how and in what conditions many Canberrans would live.
Almost from its very inception, public housing was a vital part of Canberra's development. Unlike in other cities, where it existed to provide basic accommodation for those who could afford it themselves, Canberra's program provided homes for all classes of society, and in all kinds of forms.
There were hostels and hotels for politicians and single public servants, flats for young couples, workers' cottages for those in construction, and houses of varying sizes for the growing public service.
In fact, it wasn't until well into the 1970s that the number of privately built homes surpassed those built by government.
But the end of World War II kicked off a genuine housing crisis, with public servants pouring into the capital. Single dwellings, so long the home of choice for planners, wouldn't be enough to meet the growing waiting list for accommodation.
To make things worse, since the war, building costs had gone up, and there was a shortage of materials. Building outwards was not yet a viable option, and density was the answer. Blocks of flats started appearing - something barely conceived of in Canberra's earliest years.
The famous prefab cottages - quick, cheap fibro structures designed to be temporary - were down in the lowlands of Narrabundah, hidden from the ceremonial precincts.
More visible were the tall and compact red-brick duplexes, the first lot of which had been built in the 1920s in what was then called Blandfordia, just south of the Manuka shopping precinct, followed by a series in Reid.
The Depression and the war intervened, but the English-style duplexes were still considered an effective way to house people quickly in the postwar years.
Today, you can see plenty of these beauties, built at different times, scattered in various pockets of the Inner South and North - Narrabundah, Yarralumla and Deakin, and also in Reid, Campbell, Dickson, Downer and Lyneham. They tend to be in small clusters, and vary in attractiveness according to the era in which they went up.
Nicholas Brown, professor of history at the Australian National University, lives with his wife, Susan Boden, in an original version on Sturt Avenue, the road that effectively divides the sprawling suburb into its unofficial high and low ends.
Originally two bedrooms, and lived in for many years by the original family, who had eventually bought it from the government, it has all the classic hallmarks, but extended and modernised over the years. There's a tall stairwell, room under the stairs, gracious high-ceilinged rooms, a fireplace and very small bathroom.
But there are period details that live on; Brown particularly likes the brick detailing around the doorframe and quirky tiling around the living room hearth.
As a historian of early Canberra and of the public service, Professor Brown likes to imagine what the criteria were when it came to allocating houses to Canberra's newest residents, as they fetched up in its muddy paddocks and treeless streets in the late 1940s and early 1950s.
"It's a standard British, Garden City model, except if you think about Garden City streetscapes in outer London suburbs, or any metropolitan city that was developed in Britain around this time that has that model of the duplex," he says.
"They tend to be a little bit more middle class, whereas if you think about the Narrabundah houses, particularly the two-bedroom houses, they're not middle-class at all. They're pretty austere."
With just two bedrooms and one bathroom, the assumption must have been that such a home was adequate for a certain type of working-class family.
"It shows the kind of class hierarchy, too, that some families only need one bedroom to bring up their families. It would be interesting to know what determined who got allocated a three-bedroom model," he says.
Those days are well in the past, and today, classic Canberra duplexes occupy most rungs of the housing ladder. They pop up for sale all the time - one of the originals in the completely intact strip in Narrabundah's Vaughan Gardens recently sold for more than $1.3 million, while a three-bedroom specimen in Campbell recently sold for $1.5 million, a standard price for both the suburbs and the style of house.
There are also many dilapidated versions occupied by generations of students in Lyneham, and million-dollar restorations in Yarralumla and, indeed, throughout Narrabundah and Griffith.
None are heritage-listed, and some famous examples of developmental overreach illustrate this oversight. In 2013, for example, a woman in Yarralumla sat cowering with her children as the other half of her duplex was demolished without warning, leaving gaping holes in her walls. And, in 2018, a group of four Narrabundah duplexes were assessed by the heritage council as having no historical significance, more than a year after they were demolished.
