UPDATED 12.32PM A South Auckland motel is about to become social housing, but the Government is promising vulnerable people won't be dumped there long-term.

The ten unit motel in Takanini has just been bought by Housing New Zealand, and the Government body isn't ruling out buying up more motels in the future.

Social Housing Minister Paula Bennett said they're building permanent housing, but they also need fixes right now.

"In the meantime, that doesn't help the woman and her children that needs to leave tonight because of a domestic violence incident and need somewhere to go tomorrow."

Controversially, the motel is already being used as long stay housing, with some residents worried they'll have nowhere to go.

But Ms Bennett said they'll work with the existing residents, who could get long term accommodation, while the motel is kept for emergencies.

"So we would like to see that being used for people up to 16 weeks, and then transitioning into permanent housing."

Labour's Housing spokesperson Phil Twyford said the motel is no substitute for a major Government-backed building programme.

"That's what this Government should have done years ago - instead of selling off state houses, they should have been building large numbers of additional state houses.

"If they'd done that, we simply wouldn't have the homeless crisis that we see now."