Australia's most expensive house, Point Piper estate Fairwater, sold to techie Mike Cannon-Brookes

Tech billionaire Mike Cannon-Brookes and his wife Annie have bought Australia’s most expensive house, Fairwater, ending more than a century of Fairfax family ownership.

“We are delighted with the purchase of Fairwater for our young family and look forward to continuing the legacy of this beautiful Sydney home,” Cannon-Brookes said in an exclusive statement to Domain on Thursday morning.

“We love the idea of raising our four young children in this historic property, filling the house and gardens with love and laughter through the years.”

• Related: Sydney’s most expensive residence sold in $140m+ deal

It took a little more than two weeks for the 1.12 hectare estate to exchange, and sources say it is expected to transact at close to $100 million given how quickly it sold.

The largest privately-held property on Sydney Harbour, and one of the most significant heritage houses in the country, was sold by the executors of the estate of the late Lady (Mary) Fairfax, who died a year ago, aged 95.

For 20 years Fairwater was not expected to be sold after a report cited plans by Lady Fairfax to bequeath it to the people of NSW, but that report was never confirmed and the executors listed it with Ken Jacobs, of Christie’s International, earlier this month.

Mr Jacobs was unavailable for comment at the time of publication, but multiple sources said the property exchanged on Wednesday night.

The sale smashes the $71 million record set last year by the Fairfax family’s Elaine estate next door sold by Jacobs to tech billionaire Scott Farquhar, co-founder of the software giant Atlassian.

Fairwater and Elaine have stood as monuments to the world’s longest-running media dynasty for more than a century since they were purchased by brothers Sir James Oswald Fairfax and Geoffrey Evans Fairfax, grandsons of The Sydney Morning Herald co-founder John Fairfax.

The deal effectively passes the neighbouring trophy estates on 1.82 hectares to the 38-year-old tech billionaires and co-founders of Australia’s biggest tech success story, Atlassian.

Atlassian was founded in 2002 using $10,000 in credit card debt and the co-founders debuted on the BRW Young Rich List in 2007. Following Atlassian’s float on the Nasdaq exchange in 2015 and its surge in value Cannon-Brookes and Farquhar are now ranked in the top 10 richest people in Australia.

Elaine was the longest held by the Fairfax family, purchased in 1891 by Geoffrey Fairfax for £2100 and Fairwater last traded in 1901 for £5350 when purchased by Sir James.

​Fairwater, described in heritage records as “medieval and Queen Anne inspired”, was built in 1881 for stockbroker Francis Edward Joseph and designed by leading architect of the day John Horbury Hunt.

After Sir James died in 1928 it was left to his widow Lady (Mabel) Fairfax, who in turn left it to her son Sir Warwick Fairfax after she died in 1965.

Sir James commissioned additions in the Arts and Crafts style in 1910 by Manson and Pickering architects.

Sir James died in 1928 and his widow Lady (Mabel) Fairfax followed in 1965, leaving the family home to their son Sir Warwick Fairfax.

Sir Warwick was knighted in 1967 and moved to Fairwater with his third wife Lady Fairfax the following year.