The Healthy Home Standards are a vital tool for charities helping people living in cold, damp homes, an advocate says.
The government's Healthy Homes Initiative is being credited with improving vulnerable people's health, but those providing support said many whānau were still suffering in cold, damp houses.
One of the report's authors would like to see it expanded, saying it has provided extremely good value for money.
The programme run by Health NZ arranges for health and sustainability organisations to assess the homes of low-income families and provide improvements like new curtains, insulation and draft stoppers.
It's helped 142,000 people in 11 regions to date, and will expand to cover the whole country by the end of the year.
"[It's] looking at the structural issues of why things are getting worse" - Sustainability Trust chief executive Georgie Ferrari
The Sustainability Trust, a Wellington-based charity, has been among organisations providing those improvements to thousands of homes.
Chief executive Georgie Ferrari said the programme was a good example of an effective early intervention public health initiative.
"This is a programme that looks to get in early and stop things before they get worse and [it's] looking at the structural issues of why things are getting worse," she told Morning Report.
She said an example of situations they had seen were tenants moving into cold damp rentals and having to tuck their children into mouldy rotten bedding. Because the tenants were on low incomes they could not afford to buy better mattresses.
The programme allowed the charity to buy new bedding and advocate for the rental to be improved to prevent the problem happening again.
Ferrari said it was vital that the core issues causing people to live in damp cold homes were addressed and the Healthy Home Standards had helped the charity advocate on behalf of tenants to get improvements.
"They've given us some levers that we can pull and advocate for those tenants. It's often tricky to advocate for tenants because they're still nervous about the security of their tenancy if another party comes in but we always do it in conjunction with the whānau we're working with."
The laws say there must be insulation and no water ingress that makes it damp and mouldy for the tenants, for example.
Most landlords wanted to do the right thing so it was just a matter of working with them, however, there was "a long tail of landlords" who weren't on board with making improvements, Ferrari said.
While it was hard work her charity was committed to seeing it through.
Another problem was cheap heating appliances - referred to as "vampire appliances" because they sucked up electricity without providing adequate heating.
A tweak to the standards that insisted landlords had to provide curtains would be useful, Ferrari said. With that change people might not have to use so much heating.
The standards are due to be reviewed over the next year or so and she hoped that would be among changes.
"There are a lot of loopholes in the standards as well. You can get exemptions - there's a whole range of things people can use if they don't want to be responsible landlords."
'Extremely good value for money'
The Healthy Homes Initiative is so effective it should be available for more New Zealanders, one of the report's authors says.
Nevil Pierse from Motu Research and the Department of Public Health at Otago University said the most important factor in the programme's success was having an adviser coming into the home rather than providing advice from a distance.
The provision of insulation was another key factor, he said.
There were long-term gains that could be measured over three years with reduced hospitalisations, better school attendance and more people in employment.
"So it's really showing that when parents aren't sick, when their children aren't sick that they can get more things done and the kids are more often in school and [they're] in work so it's really holistic in that it's improving the family's entire wellbeing."
Pierse said it was critical that the programme operated on a local basis. "Local people going into local people's homes so there is some connection ... and then the whānau are ready to listen and they're ready to embrace the interventions you're trying to deliver, so it's working with the whānau."
He was in no doubt that the programme should be expanded. The entry criteria could be changed so that people on higher incomes qualified for assistance.
"This is an extremely good value for money programme and it's worth expanding it to other people."
"It's worth expanding it to other people" - Report author Nevil Pierse from Motu Research