Almost five months after their roof blew off, residents of a western Sydney apartment building have suffered another setback, with last weekend's storms adding an extra $1 million to the already hefty damage bill.

Key points: Fifty-three owners may have to wait until Christmas to move back in

Fifty-three owners may have to wait until Christmas to move back in Some residents have been living in rented accommodation since January

Some residents have been living in rented accommodation since January Residents are caught up in legal wrangle over who should pay for damage

The latest damage has also delayed plans for the 53 owners to move back in and they say it may now be Christmas before they will be able to return to their homes.

Alina and Parag Piya own an apartment on the ground floor. Until now it had escaped untouched.

But last weekend's downpour seeped down four storeys and through their ceiling.

"It was a huge tension, a huge stress for us, thinking what might have happened to our apartment. Did the water get in? Is our furniture damaged? It was really tense," Parag Piy said.

Since the end of January, the couple and their three-year-old daughter have been living in rented accommodation.

"It's been five months now, mentally, financially we're really stressed, it's not an everyday thing you have to live through," Mr Piya said.

The apartment owners are caught up in a legal wrangle over who should pay for the damage to the roof.

The insurance company AIG is refusing to foot the bill, saying it was structural defects and not the January storm that caused the original damage.

An inquiry is exploring the now defunct Auburn Council's handling of the development.

The developer was former Auburn councillor Ronney Oueick.

'We'll pay for this for the rest of our lives': resident

Apartment owners are considering legal action.

In the meantime, they have banded together and taken out a $2.4 million loan to pay for a new roof.

They have employed a builder and are hoping a covering will be in place within weeks.

Alina Piya owns an apartment on the ground floor. ( ABC News )

"We're the least at fault and the least able to pay and yet here we are bearing the responsibility," Phil Thai, an owner who is on the executive committee of the strata plan, said

"There's that continuing uncertainty of who's going to pay, will anyone pay, will we be left to foot the bill," he said.

Local MP and State Opposition Leader Luke Foley said the residents should qualify for emergency financial assistance.

"The circumstances are unique and the circumstances are extreme, and I want our state government and our Premier to step in," he said.

In a statement, the Premier Mike Baird said: "My heart goes out to these families and it is sad that Labor seeks to exploit their plight for political ends.

"The families have received assistance from the Department of Family and Community Services and from Legal Aid and are currently seeking legal redress."

In the meantime, life for many of the owners has been put on hold.

"My husband and I have no savings, all our money is going to pay mortgage and rent," Lukshini Rasakulasingam said.

"We can't start a family, this is what we'll be paying for for the rest of our lives."