Why Your Wood Heater Is A Bad Idea

Why Your Wood Heater Is A Bad Idea

At this time of year there’s nothing better than being warm and cosy in front of a blazing wood fire. But take a moment to walk outside and check your chimney — it could be polluting an entire neighbourhood.

Wood heater picture from Shutterstock

I have to declare that I am ambivalent about this. I love nearly every aspect of wood heaters. The sight, the smell, the heat they produce, the link with a beautiful and living source of fuel.

When my family moved to Tasmania a few years ago, we found a lovely older style house with high ceilings and verandas that was heated with wood. The fire warmed the entire house and I was delighted with it. But there was a problem.

At the time of our move, I was completing a doctorate on the health effects of bushfire smoke — a small niche within the giant corpus of global research on the health effects of air pollution.

Smoke harms

Bushfire smoke and the smoke produced by wood heaters have much in common. They, along with tobacco smoke, are examples of biomass smoke — emissions that come from burning organic matter such as grass, leaves or wood.

Biomass smoke is a toxic soup of hundreds of different chemicals that includes many well-known toxins and carcinogens.

The population-wide health impacts of outdoor biomass smoke have been far less extensively studied than the more dominant causes of urban air pollution that mostly comes from burning fossil fuels for industry or transport. But the evidence is growing.

There’s absolutely no doubt about the harm woodsmoke does to lungs in those who are susceptible, from precipitating asthma and worsening existing respiratory diseases in the short term, to causing chronic lung diseases and lung cancer in the long term.

In cities where wood is the main fuel used for home heating, outdoor smoke pollution concentrations have been directly associated with hospital admissions for both heart and lung diseases. Even relatively brief (one or two days) exposure to outdoor biomass smoke from bushfires has a measurable impact on population health.

My research has shown that on days that Australian air quality standards were exceeded because of bushfire smoke, mortality rates increased by about 5 per cent. And others have found that out-of-hospital cardiac arrests on such days increased by almost 50 per cent.

Lessons from Tasmania

The Tasmanian city of Launceston achieved notoriety during the 1990s as one of Australia’s most severely polluted cities, with air quality that didn’t come anywhere close to meeting national air quality standards for most of winter.

A coordinated series of government interventions from 2001 included an education campaign to reduce the proportion of poorly operated heaters belching visible plumes of smoke, and a buy-back scheme that saw the absolute number of wood heaters fall by half.

The result was vastly improved air quality. The average winter concentration of particulate matter fell by 40 per cent — an improvement large enough to see a substantial drop in mortality. Winter deaths from heart diseases were reduced by 20 per cent and winter deaths from lung diseases fell by 28 per cent.

In absolute numbers this translates into approximately 30 premature deaths avoided every year from the inner city population of 70,000 people.

Deaths are the extreme and uncommon end of the spectrum of health impacts from air pollution. But they represent the tip of the iceberg of community impacts. For every death avoided, there will also be far greater numbers of avoided hospital admissions, ambulance call outs, GP attendances, days unwell and absences from work or school.

Mitigating risks

In rural areas, wood is often readily available at minimal cost and represents the most affordable option for many people. Yet wood smoke clearly extracts a large health toll from the community, even in very small population centres.

So how can we minimise these impacts? The value of insulation and choosing energy efficient fuels are well documented but the immediate costs are beyond the reach of many families.

Systematic government programs clearly have a role and are likely to be highly cost effective. Individually, wood heater owners can do a huge amount to reduce the pollution they cause.

Even modern certified heaters are capable of producing orders of magnitude more pollution when burning inefficiently compared with bright, flaming, efficient use.

Inefficient burning results in the emissions of potent greenhouse gases such as methane and wastes energy that could otherwise be heating the home. You can find detailed advice on how to minimise pollution from your wood heater on many websites.

Probably the single most important thing to remember is to open the air vent fully each time new wood is added to the fire and then allow it to burn hot for 20 minutes before reducing the air intake. It’s especially important never to completely close the air intake.

If a flame is not present, wood gases — invisible in the fire box — will condense into microscopic particles that form thick smoke plumes that will continue to pollute your neighbourhood throughout the night while contributing very little heat to warm your home.

Smoke should almost never be visible from a working chimney, but I still count numerous thick plumes on my way home every night. We clearly have a long way to go before efficient operation of wood heaters becomes the norm.

I still love wood heaters, but owning one meant owning its pollution. Even if we achieved consistently prefect operation, I knew that other heating choices would be better for the environment and the community. We replaced our heater with a less polluting alternative. It’s a bit less evocative but does come on at the flick of a switch.

Fay Johnston is Senior Research Fellow, Environmental Epidemiology, Menzies Research Institute Tasmania at University of Tasmania. She receives funding from the Australian Research Council, the National Health and Medical Research Council, the Victorian Department of Environment and Primary Industries and the Bushfire CRC. The ConversationThis article was originally published at The Conversation. Read the original article.


  • If you can afford to install Reverse Cycle Air Conditioning you will save money have a more efficient heating and cooling system and you can set when it starts and stops. We put in a descent r/c-aircon (Daikin) when we moved into our house back in the late naughties and it has saved us a fortune. Plus you have the added bonus of not having to source timber.

  • I am sure that many others like myself would like to use a cleaner fuel and one that is less time consuming and much less hard work but please keep in mind that most rural and regional properties do not have access to natural gas and the cost of bottled gas or electricity is too high to use as a substitute for wood.
    I live in a small town about 100kms from Melbourne and within 2 kms of a gas plant but we do not have access to natural gas.

    • We have the same problem and, honestly, a wood fire loses its romantic appeal after the first week of blisters from splitting wood, cleaning grot off your clothes and hands, and coming home to a freezing house because you didn’t want to waste wood keeping the fire burning all day. Fires are difficult, especially when you don’t have the money to buy tonnes of dry Barmah forest to burn.

      We too have a gas line within a few clicks of town but no access. Welcome to the realities of living in rural Victoria.

  • Currently, in Tasmania, wood heating is far cheaper than any form of electrical heating. It is unreasonable to expect people to ditch wood for electricity in these situations.

    The Launceston problem was due mainly to environmental factors linked to the city’s location that exacerbated the smoke problem, rather than just the use of wood heating. However, there was a considerable impact from the buyback scheme. Many poorly maintained heaters were removed, but the program was flawed in that it did not specifically target offending installations.

    • A government body half-ass approach to implementing something to resolve a not very well detailed study of a apparent issue? My word!

  • Been living in Launceston for 2 years now, and I must say that the smoke is noticeably worse than anywhere else I’ve lived. Maybe I should get out before my childhood asthma problems resurface,..

    • not a bad idea. even if they arent exhibiting severe symptoms at the moment, you dont really know what toxins are settling in there systems that could cause issues later on in life.

      • Yeah, I mean, if you use an electric heater, sure you are helping the environment, etc..

        But your power bill goes through the roof… absolutely… I got a power bill last year that was $1200 in winter and I live by myself… about 70% was heating…

      • 101 rehashed versions of the Harvard Six Cities epidemiology studies isn’t close to getting me convinced and neither should it convince anyone else. We wait for the conclusive evidence that particulate matter and more specifically, the smoke from typical wood heating is something worth regulating in respect to ‘real’ health risks at all. Warm dry homes, mixed heating methods – an increase of them I’m sure will bring down one side of the data comparisons linked to the evil PM.

  • Rural properties – sure, that’s fine – burn wood, it’s sitting around for you and you don’t really upset anyone by doing so.
    In city suburbs – now that’s disgusting and it’s a practice that should be made illegal.
    The UK ditched smoky coal burning fires way back in the 1960’s. In Sydney, Perth, Melbourne etc, you can still pollute the cities with your wood burning stove.
    I speak as someone who once moved house just to get away from the woodsmoke generators living next door. They refused to moderate their obnoxious burning behviour.
    So my kids (young at the time) choked on smoke through every winter. All our washing hung on the line stank of wood smoke. If we opened windows to air the house the place filled with smoke. Foul.
    Amazingly there was nothing the local environmental laws could do to help us. That is why the practice should just be made illegal within a certain radius (let’s say 50km) of any CBD.

    • Shouldn’t be a distance thing, should be based on natural gas supply. If you have natural gas available to your home, use it!

      • My point is that even in areas where there are gas pipelines nearby, connections are not offered to consumers in those areas. I’d be more than happy to use natural gas if I could!

  • There are dozens of efficient alternatives to fireplaces which still use burning wood to heat.
    Have a look at (google) rocket stoves and wood gasification systems. Alternatively you can make your own charcoal. You can make all these units yourself, they are all more efficient and clean than an open fire.

  • It’s a good thing, it keeps Santa Claus out, and if it gets a little too dirty, I’ll just call Mary Poppins and her chimney sweeping buddies

    On a serious note

    Rocket Mass Stoves are a good alternative to open fires
    They uses about half the fuel and produce much less smoke
    Not only can you use them for cooking, but you can use them for heating too

  • Nope, as per the comment above, I found coal burning fireplaces still available, and widely used in the uk. I find that a good wood based fire can be reasonably efficient though it depend on the design of the house.. MOST houses in australia do not have natural gas.. and wood based heating can be very appropriate in large chunks of Australia. Especially while there is a carbon tax on electricity and none on wood..(renewable anyone)

  • id love to know what toxins come out of wood when burning. i live on a 3200m2 block in Adelaides north-eastern suburbs (built up) area. we love our wood heater because its a different type of heat to what our split system throws out. and we find ourselves getting sick when we have our split system on for heating all the time. not only that, we have a stack of red gums and melaleucas on our property that are right there to use as fuel.

    yes pollution definitely concerns me and i would stop it if it wasnt expensive to run electric heating all the time and if we had access to natural gas.

  • Wood heaters should be banned in all urban areas – been complaining about my neighbour’s filthy smoke stack for about 6 years – local council won’t do a thing about it, neighbour couldn’t care less. Would love to sell up and move, but there is no guarantee that, wherever I may move to, that I won’t end up with another smoke stack next door in the future. Disgusting.

  • Domestic wood heaters should be banned in all urban areas across Australia
    where residents are likely to be subject to the combined effect of numerous wood heaters
    for months on end. If only everyone appreciated the smell of fresh air. Wood smoke
    is definitely health hazardous and the smell alone is terrible.

  • I live in a very remote part of Tasmania (probably 10 permanent residents in 10 square Km. We have a woodheater, but have invested in a Lopi that produces bugger all emissions and is very fuel efficient. I think woodheaters, even in small towns are a terrible thing. Our nearest town (thankfully 1/2 an hour’s drive away) has a population of 129 people, yet in winter on still days there is a pall of woodsmoke that hangs over the town. New Norfolk is truly awful – I drive through there early in the mornings in the winter and you can see the thick black cloud hanging over it. I’m grateful for where I live that I can have a woodheater as any type of blower heater (and for me heat pumps high on the wall are the worst) cause me to have migraines. If I lived in the city I’d have to live in a permanent freeze.

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