Prices for Canberra's most premium homes have grown more than 120 per cent in the past decade, outpacing the price of median properties across the capital.
While local real estate agents say there is far more luxury price growth to come, affordable housing advocates believe it is time for zoning reform to reverse the trend of "protected mansion" suburbs.
In the past 10 years, the median house price has grown about 92 per cent, while the price of homes in the top five per cent of the market have risen by about 121 per cent, data by Ray White has revealed.
Units in the top five per cent of the market had also outperformed, growing about 69 per cent versus 51 per cent for median units.
Ray White Group chief economist Nerida Conisbee said while luxury homes across Australia had outperformed they had also been more volatile.
"During the pandemic, they increased far more than more affordable properties. But they also saw a much greater decline in 2022," she said.
"Timing the purchase of a luxury home appears far more important than it does for buying one closer to the median."
The data shows while the median house price in Canberra is about $1,038,000, the median for the top five per cent of homes is about $2,054,000.
The median unit price is $623,000, compared with the median among premium units of $1,146,000.
Lotto winners, developers, sports stars buy big
So who is buying these multi-million-dollar mansions?
It's a mix of people that has changed over time, Blackshaw Manuka managing director Andrew Chamberlain said.
"We've sold homes to lotto winners, to cryptocurrency traders, to doctors, to sports people," he said.
"Property developers are also very prominent."
The "IT boom" brought with it technology professionals, Mr Chamberlain said, while the days of Super League saw "a lot of rugby league players with deep pockets".
As the buyers have changed, so too have the properties at the premium end of the market.
Mr Chamberlain said premium sales were, for a long time, driven by the size of the land.
"For some time, the fact that you could actually buy a two-acre block of residential land within a 10-minute drive of the city was absolutely unique in the ACT as opposed to virtually any other capital city, I'm aware of, around the world," he said.
As building costs increased, there had been a shift in the top end of the market, Mr Chamberlain said.
Today, buyers were paying a premium for large, modern homes built to premium standards but not necessarily on large blocks of land.
Mr Chamberlain said the gap between premium and median priced homes in Canberra was likely even wider if you looked beyond the sales results.
Take for example 7 Tennyson Crescent in Forrest which sold in 2017 for $6 million.
"That's Forrest's second biggest block of land at just under 5000 [square] metres," Mr Chamberlain said.
The buyer is understood to have spent in excess of $9 million building the house that stands on it today.
"There's not far off a $15 million purchase without it being reflected in the actual transactions," he said.
Call for 'common sense zoning reform'
Howard Maclean, convenor of affordable housing advocacy group Greater Canberra, said it was no surprise to see a large appreciation in premium homes, given how land values have risen.
He said Canberra's zoning has only strengthened premium property prices.
"The reason why we have these very large mansions in Forrest, that are always going up in value, is, legally, it's only ever allowed to be mansion, it's only ever allowed to have one dwelling on what can be a two- or three-thousand square metre parcel," he said.
"Because it can only ever be inhabited by one family that effectively cuts off the competition and you end up with a kind of protected mansion area which is in practice what a lot of Yarralumla, Deakin and Forrest in particular are."
Mr Maclean said "common sense zoning reform" would allow more medium-density housing to be built in suburbs with sprawling blocks.
Greater Canberra has teamed up with other Canberra community organisations and businesses to call for zoning reform that would allow townhouses, terraces and dual occupancies to be built in all RZ1 zones, where only detached houses are permitted.
$10 million sale could be ahead
Canberra's residential sale record remains at $9 million, which was set in 2022 with the sale of a home on Empire Circuit in Deakin.
Mr Chamberlain had falsely predicted Canberra's first $10 million house sale last year, but said he was backing it again in 2024.
Duncan Macdonald, principal of Bastion Property Group, agreed, saying there was "quite a depth of buyers" in the top end of the market.
"I wouldn't be surprised to see sales in excess of $10 million in the next 12 months if the right property was to hit the market," he said.