Labour leader Andrew Little says figures showing it was taking an average of seven months to house people who reported living in cars were "disturbing."
Government figures show in the three months to June it took an average of 217 days to rehouse 35 people or families who reported cars as their accommodation and had applied for housing.
That was an increase from 108 days it took to rehouse 41 people in cars in the three months to December 2015.
The information also showed it took an average of 157 days to rehouse 11 people who reported living in tents or public places in the three months to June - up from 99 days for 17 applicants in the quarter to December 2015.
The figures were for applicants who recorded cars or tents as their accommodation at the time they went on the social housing register but did not mean they had lived in cars or tents for the entire period. It was possible they had moved into emergency housing before a more permanent home was found.