Auckland Council has stopped work on four or five house projects following an Environment Court decision affecting more than 400 home owners in the city's older suburbs.
About 430 home owners will have to reapply for resource consent after a court decision now requires greater scrutiny for building projects in special character areas such as Ponsonby, Grey Lynn and Parnell.
The problem consents relate to areas deemed to be of "special character" under the Unitary Plan.
Auckland Council admits it misinterpreted some aspects of the Unitary Plan rules when the consents were originally granted.
The council concedes that some of the home owners may not be granted consent when they re-apply.
The council sought advice on the interpretation of the rules in the Unitary Plan for the special character area overlays and the single house zone, which created some uncertainty about which should take precedence.
Following external legal advice, the council sought clarification from the Environment Court, which agreed the rules were not clear.
The court decided both set of rules should be applied to resource consent applications.
Of the 430 resource consents potentially impacted, 137 properties have been issued a building consent and work may have started on their properties.
The council is writing to all the affected property owners, offering to issue them with new resource consents at council's expense. This will avoid them facing a possible judicial review.