Cold, damp and mouldy homes are a major problem for up to 140,000 Kiwi children and housing costs eat up over half the pay cheques of the nation's poorest.

These are some of the revelations reported in the latest Household Incomes Report which looks at indicators of inequality and hardship.

While the median household income has risen by 3 per cent in the past year so have rates, mortgages and rents.

One third of households spent more than 30 per cent of their disposable income on putting a roof over their heads. This was most marked by the least well off who shelled out 51 per cent of their income on average for housing.

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The overall figure for under 65s was 21 per cent, up from 14 per cent in the late 1980s.

Prime Minister Bill English agreed the cost of housing was a huge issue. He said that was a core reason why National increased the accommodation supplement as part of its $2 billion Family Incomes package in Budget 2017.

"[The report] shows there's been an uplift in real incomes since 2008. Which is better performance than a number of similar economies.

"But it also shows the vital importance of getting more houses on the ground faster... In the long run that's how you deal with housing costs."

"A recipe for growing poverty" is what Green Party co-leader Metiria Turei called the housing crisis combined with low incomes that were displayed in the report.

"Housing costs are eating into families' budgets at a rate we've never seen before.

"New Zealanders living in cold damp housing know that they are paying too much to live where they are, yet they are powerless to change it."

She said New Zealand needed a Government that would build thousands of affordable homes, crack down on speculators and tax property fairly.

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Social Housing Minister Amy Adams said the report didn't take into account recent changes in the increase in benefits and the $100 million Housing New Zealand has spent on improving its housing stock .

"Housing New Zealand have completed the retrofit of almost all of their houses now with full insulation, thermal curtains and a solid source of heating. And that hasn't been picked up."

The median household income is now $76,200, or $37,900 per adult. Up from $67,100 in the 2009 Household Economic Survey.

The report highlighted housing quality issues, especially for children. Around 110,000 children live in damp and mouldy conditions, 140,000 have issues with keeping warm in winter and 75,000 experience both issues.

Those in the lowest well-being quintile (20 per cent) experience 80 per cent of the problems.

The report used data from Statistics New Zealand's 2015-16 Household Economic Survey to update the previous report in the series which had information to 2015.