The novel, Towards Another Summer, is so revealing the one-time Shore resident didn't want it published while she was alive, says her niece and literary executor Pamela Gordon, who once worked at the library.
"It's quite clearly based on her - on a weekend she spent at someone's place and on her childhood. The picture we see in the book is of a woman who is very shy and incredibly sensitive and observing everything with a very clear eye."
Towards Another Summer follows aspiring author Grace Cleave as she holidays in the north of England.
It explores her longing for a place in the world and almost unwelcome affection for a homeland where she had been thought crazy.
The book takes an unflinching look at its protagonist as she launches into perceptive and sometimes comical self-examination.
The themes of homesickness and belonging come from Frame's own experience around the time it was written in 1963, says Mrs Gordon.
Then Frame had been living overseas for eight years and was writing The Adaptable Man.
While on holiday at a friend's house she began reminiscing about her homeland.
"The novel speaks about someone learning about social convention and wondering where she fits in. That was what happened to Janet Frame," says Mrs Gordon.
Frame uses magical realism throughout the book with Grace described as a migratory bird, an image that will be familiar to many Kiwis, says Mrs Gordon.
"There's this longing for her homeland and also criticism of it, which Kiwis on their OE could relate to.
"It's like she really is this migratory bird, only no one else knows it. It's a good metaphor because where does a migratory bird belong, where is its home?"
Frame was born in Dunedin in 1924 into a working class family.
She experienced tragedy as a child when two of her sisters drowned in separate incidents.
She was later committed to a mental hospital where she had more than 200 shock treatments.
She avoided a lobotomy when her first collection of short stories won a prestigious literary award.
Later she lived in an outbuilding at author Frank Sargeson's house in Takapuna and became a frequent patron of Takapuna library.
Toward Another Summer was found among Frame's manuscripts after she died in January, 2004.
Although she never kept it a secret, Frame resisted the urge to publish it while she was alive, says Mrs Gordon.
That doesn't mean she wanted it closeted up or destroyed after she died, she says.
"I'm quite sure she wanted it published. She thought some works were better published after you're dead."
Frame eventually returned to New Zealand to live in Northcote with the Gordon family.
Her strong North Shore connection persuaded publishers Random House to launch Towards Another Summer in Takapuna.