Civil Defence says 22 homes face demolition following the tornado that ripped through West Auckland.
About 50 houses in Hobsonville and Whenuapai are still without power after the storm that claimed three lives on Thursday.
Civil Defence controller Clive Manley said 317 of the 510 homes inspected were found to have minor or moderate damage.
Another 22 were so badly damaged they are likely be demolished or will need major repairs.
"They are uninhabitable, they're not safe to be in," Mr Manley told AAP. "Those decisions on what to do will be made by their builders or insurers, depending on who owns them.
"They have to decide whether to demolish or repair, they're that seriously damaged."
Mr Manley said no further reports of looting had been received after increasing the police and security presence in the affected areas.
In one case, Civil Defence was told thieves who posed as contractors assisting in the clean up entered a house and took personal items.
There was also a report of another case, but Mr Manley says they have been unable to confirm it.
Three men died in the tornado: Tom Stowers, 42, Brendon Johnson, 22, and Keith Langford, 60. They were killed by falling concrete slabs at the site where Hobsonville High School was being built.