Home fires are a significant source of air pollution in some Otago towns.

We all breathe what we burn, so here are some Burn Dry, Breathe Easy tips that will ensure you get more heat from your firewood, and help reduce air pollution in your town.

Switching to a higher performing, or approved heating appliance can also greatly improve the air quality. 

Burn Dry, Breathe Easy tips

  • Always make sure the wood you are burning is dry. It’s better for you, your home and the environment.
  • Stack your firewood off the ground, out of the rain and with plenty of airflow so it dries faster.
  • Purchase your firewood before Christmas to allow it dry out before the following winter.
  • Use a wood moisture meter to check if your firewood is dry enough to burn. Less than 25% moisture means more heat and reduced smoke.
  • A well-built fire of scrunched up paper, kindling, and firewood with plenty of airflow ensures a well-heated home and less smoke. 
  • Don’t burn wet or green firewood, treated wood or household rubbish as they can release harmful toxins into the air.  
  • To reduce smoke overnight, make sure you can still see flames when you turn your fire down.

Below you’ll find additional information, building on tips above.

Only burn dry wood or paper

A hot fire built with dry wood produces very little smoke. If you see dirty smoke coming from your chimney, it’s a sign your fire doesn’t have enough oxygen or you’re burning something toxic. Both release pollutants into the air. 

Burning dry wood gives you more heat from each log, warming your home faster. Your fire will also burn hotter, meaning less pollution. 

Have your flue swept once a year to improve air flow and help to prevent a chimney fire. 

Is my wood ready to burn?

  • Look
    • Dry wood is dull in colour.
  • Feel
    • Dry wood has a low moisture content, so it is much lighter than wet or freshly cut wood. 
  • Listen
    • When you knock two larger pieces together, they should sound hollow or produce a lighter “KLACK”ing sound. If the wood is too damp, it will sound like a dull “THUNK”. 
  • Take out the guess work
    • Use a wood moisture meter to check that your firewood has less than 25% moisture. Split a log, then take three readings from the split surface. While you could insert the pins on the meter into one end of a log, generally the ends of logs are drier than the inside. The display will show a moisture percentage. You can get wood moisture meters at most hardware stores. 

What not to burn

Burning these kinds of materials can release harmful toxins into the air. 

  • Treated wood
  • Off cuts from building sites (avoid treated wood, wood with nails, glue or other contaminants)
  • Old decking
  • Rubbish
  • Green waste
  • Plastic
  • Clothes
  • Electronics
  • Disposable nappies

Note: Burning coal is not permitted in Air Zone 1 towns:

Approved heating appliances

Different areas have different rules about the burner you can install.  

  • Air Zone 1 (Alexandra, Arrowtown, Clyde and Cromwell) and Milton: burners must have an emission rate less than 0.7 g/kg and a thermal efficiency of at least 65%. 
  • Air Zones 2 and 3 (rest of Otago): burners must meet the MfE guidelines of an emission rate less than 1.5 g/kg and a thermal efficiency of at least 65%. 

Appliances that are approved in Air Zone 1 and Milton are: 

  • Heat pumps (all models) 
  • Flued gas heaters 
  • Pellet fires 
  • Ultra-low emission wood burners

Who can I talk with about heating my home more efficiently? 

Cosy Homes Trust  

The Cosy Homes Trust offers Otago residents free guidance about how to access subsidies for heating and insulation. They also provide general advice on keeping your home warm, dry and energy efficient.  

Energy Efficiency and Conservation Authority (EECA)  

EECA’s Warmer Kiwi Homes programme covers up to 80-90% of the cost for ceiling and underfloor insulation and up to 80% of the cost of heating appliances (heating appliance capped at $3,000).  

Frequently Asked Questions (FAQs) for home heating

Page last updated 7 July 2024.