From July 1, well designed dual occupancies, manor houses and terraces up to two storeys can be fast tracked and approved within 20 days if they comply with relevant requirements in the State Environmental Planning Policy.

The State government said these housing types can help housing affordability by providing smaller homes on smaller lots that still provide amenities of a single dwelling.

They will only be permitted in R1, R2, R3 and RU5 zones under council's local environmental plan.

Not everyone is happy about the new code.

NSW Labor has called on the government to scrap or amend the code amid concerns of over-development and poor planning controls.

Amendments include permanently excluding local government areas which are bushfire prone and have already made provision for medium density in local planning rules.

The opposition also wants assurance the code does not remove existing planning controls or community input.

Labor is not opposed to medium density housing where appropriate but claims the code imposes an 'inappropriate one size fits all' approach to communities across the State without public input.

"The first time residents will know about these kinds of developments occurring next door will be when construction starts," NSW Shadow Planning and Better Living Minister Adam Searle said.

"Even local councils will not know ahead of time.

This means there will no chance that growing communities will get the social and physical infrastructure they need."

The code was set to be implemented last November but was put on hold across 46 local government areas, including the Mid Coast, following an independent review.