The commission released a lengthy report last week, which looked at how New Zealand may be affected by climate change-related risks, and where focused and co-ordinated action can make the biggest difference.
Chief executive Jo Hendy said analysis suggested acting now would reduce costs across the economy.
‘‘Focusing effort and investment on a few key things will have much wider benefits and help bring the overall cost down,’’ she said.
‘‘More than half a million buildings are already exposed to inland flooding, with at least $235 billion at risk.
‘‘If we build homes that can cope with floods and extreme weather, we’re not just protecting the building, we’re protecting people’s health, keeping essential services running and helping keep those homes insurable.
‘‘If we don’t act, costs could run into the billions and affect every part of people’s lives.’’
The commission said since 2000, the price of house insurance in New Zealand had increased by more than 900% in nominal terms.
There was a significant level of underinsurance, and homeowners increasing their excess to help reduce premiums.
New Zealand insurers rank climate change in their top five risks.
The commission said climate change would probably overtake the risk of seismic events in many locations.
‘‘The significantly increased premiums will mean households in some areas may not be able to access insurance by 2035. Risk-based pricing could also compound existing inequities if households are priced out of buying insurance and are impacted by extreme weather events.’’
Population growth was driving demand for new housing and infrastructure, and continuing the trend of increasing housing density in coastal areas.
More than 65% of New Zealanders lived within 5km of the coast.
‘‘Without stronger measures to prevent developments in highly exposed areas, this trend may exacerbate this risk,’’ the report said.
The increased monitoring of historic insurance premiums and claims was not at the point of delivering deep insights useful to the public.
‘‘While the risk to the accessibility of insurance is recognised by the government, the actions and policies currently in place focus on understanding the risk in greater detail, rather than directly addressing it.’’
The report uses South Dunedin and its response to rising sea levels as a case study.
It explains what the area faces and acknowledged the proactive and extensive work of the South Dunedin Future programme, which recognised the need to adapt in an inclusive and meaningful way.
