A "warrant of fitness" scheme for all rental housing may be on the agenda whoever wins the election in September, a new survey has found.

Documentary maker Bryan Bruce, who first raised the idea in a controversial TV3 programme just before the 2011 election, said his survey of 12 political parties last week showed "a remarkable shift in political attitudes towards child wellbeing issues since the last election".

Only Act and the Conservative Party told him they still opposed a general warrant of fitness scheme for all rentals.

National deputy leader Bill English declined to answer the survey but pointed Bruce to the Government's decision to trial a warrant of fitness on 500 state houses this year with a view to rolling out three-yearly warrants for all state houses.


Housing Minister Nick Smith said at the time: "The Government has not made any decisions about the wider application of the warrant of fitness to other social housing providers or the private rental market. Our first duty is to ensure our own house is in order."

Labour children's spokeswoman Jacinda Ardern told Bruce that Labour would require all landlords to make rental properties warm and dry.

"This ensures that we get the benefits of a warrant of fitness without the administrative cost," she said.

Most parties, this time including the Conservatives but not the Maori Party, also supported extending paid parental leave to one year.

National has so far committed only to increasing paid leave from 14 weeks to 18 weeks by 2016, and Labour has promised to increase it to six months by 2017.

There was less support for free lunches in schools.

The National Government subsidises charities run by Fonterra, Sanitarium and KidsCan, and Labour has promised to work with community groups to ensure free food in low-decile schools, but neither major party supports extending free lunches to all schools.