PRE-SET housing codes introduced by the State Government earlier this year to help builders have their plans approved by councils in as little as 10 days have proved so unpopular they will have to be rewritten, the Planning Minister, Kristina Keneally, said yesterday.

A code for single-storey homes to be built on 600-square-metre blocks, which was tested recently in 11 NSW councils, was used for only 11 per cent of the development applications in the trial, well below the 50 per cent of DAs targeted by the Government, she told a budget estimates hearing.

The Government said the codes would speed up approvals, cut costs and give certainty about building plans.

But it appears most people in the trial, which included the council areas of Randwick, Sutherland and Pittwater, preferred the slower, more expensive council DA process.

Ms Keneally said the codes would have to be made more user-friendly.

The Opposition planning spokesman, Brad Hazzard, said the codes had added to the "shambles" of the DA process.