Residents and owners of units in Sydney's troubled Mascot Towers are being assured the building is not sinking, even though an engineer found part of it appeared to be "moving in a downward motion".

The 10-year-old complex was evacuated on June 14 after engineers became concerned about continued cracking in the primary support structure and facade masonry.

Since then, residents of its 132 units have been forced to stay elsewhere, with costs quickly adding up as authorities scramble to determine who is at fault.

Mascot Towers’ coordinating engineer has now identified a new issue along the northern and eastern boundaries of the complex.

“It appears that the building is moving in a downward motion,” an update sent to residents and owners on Monday night said.

The update didn’t elaborate on “downward motion”.

A spokesman for the owners’ corporation on Tuesday said describing it as “sinking” was inaccurate.

“There has been some differential settlement resulting in the currently observed building movements, at least in part,” he said in a statement.

“But any interpretation of the building sinking at present is considered to be alarmist. The building engineers are continuing their investigation and monitoring.”

Differential settlement is when a building’s support foundation settles in an uneven fashion – sometimes causing structural damage.

Two senior geotechnical engineers have been engaged and are visiting the site this week with help from Engineers Australia, the update said.

Internal monitoring has been expanded, while equipment to measure external movement has been set up on Church Avenue and Bourke Road.

It comes after the NSW government on Sunday announced a multi-million dollar assistance package “until liability can be determined and these costs recovered”.

The package offers one-off emergency loans to cover up to $400 per night for temporary accommodation, for a period of up to three months.

But it remains unclear what will happen if no one is found to be at fault or if insurance claims aren’t paid out.

When asked to guarantee that residents themselves won’t have to pay the money back, NSW Premier Gladys Berejiklian said the government was “working through those issues”.

“The engineers haven’t yet finished their assessments,” she said.

The money for the loans will come from the interest accumulated in the NSW Government’s rental bonds fund.

Source: AAP