Cold and damp houses in Dunedin are a ''community shame'', Dunedin Mayor Dave Cull says.
Mr Cull spoke to about 40 people at Carisbrook Primary School Hall at a Child Poverty Action Group meeting in Caversham yesterday.
Dunedin had about 18,000 cold and damp homes, which could not be made warm and dry at a reasonable cost.
''We have stacks of affordable houses, but a lot of it is substandard,'' he said.
The focus on improving Dunedin's housing stock should not be on student flats near the campus, because many students considered living in a cold and damp flat a ''rite of passage''.
''If they are stupid enough to stay in those cold flats that is their problem. There are more important things to worry about ... There are a lot of people around Dunedin with no choice and too many people are unable to afford to heat their home sufficiently and poor health outcomes are the result,'' Mr Cull said.
Public Health South data revealed 30% of admissions to Dunedin Hospital were related to substandard housing.
The ''vicious cycle of harms'' created by substandard housing affected everyone in the community, Mr Cull said.
As Mr Cull spoke yesterday, Green Party co-leader Metiria Turei sat in the back row, knitting.
Mr Cull spoke of the ''cosy-home initiative'' - a charitable trust he was a member of which was working to get everyone in Dunedin living in a dry and warm home by 2025.
The trust had raised enough money to pay someone for two years to drive the project.
The position had recently been advertised, he said.
Earlier at the meeting, University of Otago Centre for Sustainability PhD student Fatima McKague, of Dunedin, said she spent this winter researching 32 households across Dunedin to reveal the relationship between energy and housing.
Of those interviewed, 17 were in rentals, seven in state houses and the remaining eight had mortgages on their homes.
Many of those interviewed suffered ''energy hardship'' and were unable to heat their house to a healthy standard.
''There is a strong connection between energy and poverty,'' Mrs McKague said.
The reasons for the hardship was energy prices, the quality of housing, income and the people's behaviour.
In Dunedin, 47% of households were experiencing energy hardship. In Auckland, 14% of households experienced energy hardship.
Dunedin had greater energy hardship because it had a colder climate and old housing stock and residents paid more for electricity and earned less than Aucklanders.
However, in many New Zealand regions, housing prices were increasing rapidly, resulting in more people renting.
Rental properties were of a poorer standard and were often poorly insulated.
''Half of the people renting are families and elderly people,'' Mrs McKague said.
About 70% of children in poverty in New Zealand live in rental properties.
Child Poverty Action Group co-ordinator Emily Keddel said housing had to be improved to change the ''terribly'' high rate of respiratory illness in New Zealand.
