Senior research fellow in the housing and health research programme for the University of Otago Lucy Telfar-Barnard said she was concerned to learn the government was considering reducing insulation requirements based on what she believed was a flawed understanding of the science.
It was reported earlier this week that Building and Construction Minister Chris Penk was considering rolling back standards introduced last year after being approached by a builder from Tauranga who suggested they were too expensive and meant houses were too hot in summer.
Ms Telfar-Barnard said the government’s thinking appeared to be focused on only the warmer parts of New Zealand and was based on a poor understanding of science.
"If someone doesn't have a good grasp of building science, there’s a simplicity to thinking, ‘oh, if it's too hot, then it must be the insulation’, without thinking further about where the heat is coming from," Ms Telfar-Barnard said.
She was worried any roll-back would particularly affect people in colder climates.
"I'm concerned that it if a local Dunedin developer came forward saying, ‘oh yeah, it's costing us too much money as well’, then they might look at rolling it back in the South, too."
Improving these standards was "absolutely necessary" for both home buyers and renters.
"Homes in New Zealand tend to stay up for a long time, and so you want to get it right at the beginning.
"To take shortcuts right at the start, it becomes much more expensive and complicated to try and retrofit that insulation at a later date."
Landlords buying new property to rent might not see the benefit of increased insulation, but it would mean tenants paying less for power, ultimately improving the value of the home.
"What Chris Penk has said is that they would roll back the changes.
"So, take it back to where we were before, back when we compared really poorly to other places instead of just poorly."
Ms Telfar-Barnard said, besides ceilings, New Zealand fell far behind other countries with similar climates in terms of housing standards.
