The Sydney mansions that have been sitting empty for years

Yet, dotted across Sydney, are sprawling homes worth up to tens of millions of dollars which have been left vacant to slowly decay for years.

Irving said many people would be surprised to know just how many opulent homes were sitting empty in the country's most expensive real estate market.

In many cases, the properties had been bought by developers looking to subdivide the estates and reap the profits, Irving said.

However, sometimes the developments went sour or, in other cases, simply took years and years to come to fruition, he said.

The state with the highest number of vacant homes is New South Wales, with 22,000 empty properties in Sydney alone.

One of those properties is the grand estate of Durath in West Pennant Hills on Sydney's upper north shore, which sold for $42 million in 2015. 

The historic home, which sits on 5000 square metres of prime land near Cherrybrook station, was sold to Toplace, the building arm of beleaguered Sydney developer Jean Nassif's company.

Toplace was placed into administration last year.

"The property has been sitting empty for nine years and it's probably one of the most fascinating homes I have ever photographed," Irving said.

Photos taken by Irving earlier this year show vines creeping up the windows and onto the roof of the luxury property. 

"There is a little bit of vandalism but not a great deal compared to what I normally see because it's on a residential street so neighbours still live around it," Irving said.

Further into the outskirts of north west Sydney, there were many expensive properties that had been snapped up for developments in Rouse Hill that were still yet to see the light of day, Irving said.

One of the Rouse Hill properties recently visited by Irving was sold for $7.5 million in 2019 and has been vacant for the past five years.

The white, Spanish-style mansion sits on two acres and is in the process of being subdivided into house and land packages.

Photos show the pool in the backyard filled with swampy water and surrounded by a tangle of weeds and overgrown grass.

Just across the road, a $33 million dollar property had been sitting empty for the past 18 months, Irving said.

"That one sits on five acres, and there is a development application in to build lots of tiny houses on it," he said.

While it was often not financially viable for developers to rent out the properties while they were waiting on building projects to take off, a few did try, Irving said.

But it doesn't always work out.

"One of the properties I recently photographed was a huge, eight bedroom house, absolutely massive," Irving said of the $10 million western Sydney property.

"It's owned by a developer, and they tried to rent it out. It's currently on the market for rent, but it's been vandalised and trashed. 

"Windows have been smashed and things have been ripped out of it."

Over in St Leonards, in Sydney's lower north shore, sits a 100-year-old federation home which has been vacant for about two years, Irving said.

The property developer bought all of the houses on the same street, with this particular house selling for $7.68 million in 2015.

"The house was being used as a daycare but now it's been abandoned," Irving said.

Photos show the front of the property all but obscured by an overgrown yard.

Irving said his photos of abandoned or vacant houses evoked strong reactions on social media, with his audience often becoming fascinated in the backstory of why the houses had been left empty. He is currently collating his photographs into a book.