In our Passive House design and certification work, we often push clients to ditch gas hobs and wood stoves. Usually, we talk about airtightness, energy efficiency, and the fact that a wood stove in a high-performance home is basically an “overheating machine” that might only get used once before the owners realize they’ve built a sauna. But a massive new report commissioned by EECA, Indoor Combustion in New Zealand Homes: Health Effects and Costs, just gave us 12.1 billion reasons to be even more direct.
Cost across Aotearoa – yes that’s $3Billion from gas stoves. Image from Air Quality Collective based on data in the report. https://www.theairqualitycollective.org/2025/10/08/our-commentary-and-opinion-on-the-eeca-report-on-indoor-air-quality/
The bottom line is that burning stuff inside our homes is depriving us of years of healthy living. The report estimates the total annual health costs from indoor air pollution at a staggering $6.48 billion, nearly matching the $5.85 billion cost of outdoor pollution. When you combine them, we are looking at a $12.3 billion annual hit to Aotearoa.
For a single household, a gas stove is estimated to cause $9,188 in annual health costs due to NO2 exposure. If you’re still using an open fire, that cost rockets to over $53,000 per year. Nationally, this pollution causes roughly 3,230 extra asthma cases in kids and over 200 premature deaths.
It’s a great example of why we need to reframe the conversation. We aren’t just “chasing perfection”; we are trying to stop people from poisoning themselves. While the government gambles on renewed gas exploration to fix an “energy crisis,” the real crisis is the air we’re breathing. The “holy grail” for a healthy home remains a fossil-fuel-free, airtight envelope with MVHR. Burning stuff indoors is a $12 billion health bill.
References
EECA Report: Indoor combustion in New Zealand homes: health effects and costs
RNZ: The great gas gambit
Lloyd Alter: More on particulate pollution
Air Quality Collective https://www.theairqualitycollective.org/2025/10/08/our-commentary-and-opinion-on-the-eeca-report-on-indoor-air-quality/