Human waste flowing down apartment hallways and bubbling up through shower drains, wall cracks stuffed with newspaper, crumbling building facades and balconies that need propping up.

Residents of faulty unit blocks have seized an opportunity to raise concerns about apartment building defects before a NSW parliamentary inquiry scrutinises construction standards in August.

Their revelations, detailed in submissions to the inquiry, coincide with the emergence of safety fears at a fifth Sydney apartment building, amid rising pressure on the state government to address concerns about industry standards.

In one submission, the resident of a Sydney unit said their building had been plagued with "numerous" defects. This included "odd issues with plumbing" that emerged three years ago.