Residents have been given 48 hours to evacuate an apartment complex in Melbourne's south-east after the building regulator deemed it no longer safe for occupation on Friday.

Numerous defects have been reported to the Victorian Building Authority in the 10 years since the apartments were built, including water damage causing extensive mould.

A recent investigation by the VBA found cladding on the external walls was combustible and posed a fire risk.

An apartment complex in Mordialloc has been evacuated. Credit:Chris Hopkins

Most of the 17 units are currently empty and the four remaining residents must be out by the end of the weekend.