Brett Whiteley’s 1991 painting View from the Sitting Room Window was one of the last works the celebrated Australian painter completed before his death in 1992. It depicts a dark and moody harbour view from the window of his Lavender Bay house, punctuated by white boats and golden palm trees; a pot of navy-coloured flowers sits in the foreground.

The real-life view the scene is drawn from is now protected, thanks to its addition to the NSW State Heritage Register, a list of protected places with historical, cultural or architectural importance to the people of the state.

The iconic house and the state-owned parklands surrounding it have also been added to the register, following a campaign by Whiteley’s wife Wendy. The couple shared the house for two decades and Wendy has lived in it for almost 50 years. Following her husband’s death she transformed the unused railway land below into the green and much-loved “Wendy’s secret garden”.

“You can’t control from the grave, not completely. You can make a few rules and regulations how you want your assets spent,” the 77-year-old told the ABC. “But after that it’s up to other people to love things.”

Heritage Minister Gabrielle Upton says the house, its setting and views are of state heritage significance for their historic connection to the internationally acclaimed artist. “As well as being his family home and studio, this view from his former home provided Brett Whiteley with the inspiration for much of his substantial body of award-winning and influential artworks,” says Upton, noting Lavender Bay, the harbour and its icons are all significant recurring themes in many of his paintings.

In his lifetime Whiteley won two Archibald Prizes, three Wynne Prizes and two Sir John Sulman Prizes. In March 2017, View from the Sitting Room Window sold privately for $1.5 million at a Menzies art auction in Sydney.

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Menzies CEO Justin Turner believes the new listing makes "perfect sense".

"The house is significant to Australian art and can be directly related to some of his key paintings," he says. "Wendy has done so much work on the garden ... she has turned an old railway shed into a beautiful area that the Sydney public can enjoy. We now know that site won't be developed and people can keep enjoying it for years to come, while those with an interest in Australian art can go to the place that inspired some of [Whiteley's] best paintings."