Green Building Forum - Guardian item on wood burning stoves

Guardian item on wood burning stoves

Ed Davies — Fri, 01 Jan 2021 19:04:38 +0000

Avoid using wood burning stoves if possible, warn health experts:

https://www.theguardian.com/environment/2021/jan/01/avoid-using-wood-burning-stoves-if-possible-warn-health-experts

â€œCampaigners and health experts are calling on people who have alternative heating not to use their wood burning stoves this winter amid growing concern about their impact on public health.

[â€¦]

Now experts at the Asthma UK and British Lung Foundation Partnership are asking people with wood burners only to use them if they have no alternative source of heat.

â€œWe know that burning wood and coal releases fine particulate matter (PM2.5) â€“ the most worrying form of air pollution for human health,â€ said Sarah MacFadyen, head of policy at the charity. â€œItâ€™s therefore important to consider less polluting fuel options to heat your home or cook with, especially if coal or wood is not your primary fuel source.â€ â€

Guardian item on wood burning stoves

tony — Fri, 01 Jan 2021 21:36:57 +0000

I have been saying this for 25 years, taken a lot of flack over it too.

Guardian item on wood burning stoves

WillInAberdeen — Fri, 01 Jan 2021 22:13:21 +0000

Unfortunately much of their environment journalism is reduced to rehashing press releases from pressure groups (although very worthwhile pressure groups in this case).

They could have examined the pros/cons of the upcoming EU 'ecodesignâ€™ smoke reduction standard, supposedly intended to improve on the existing DEFRA smokeless certificates by 80%; or the upcoming ban on under-seasoned firewood and bagged coal; or compared SE England with other parts of UK in terms of smoke and traffic emissions. They could have discussed that a properly insulated house doesn't need a multi-kW room heating stove. They could have discussed that air pollution in the UK is now a small fraction of what it was a few decades ago, a huge success. They could have looked at whether the electric vehicle target will reduce pm2.5 or not. But that would have made their story too complicated!

Here's a better one: https://www.bbc.co.uk/news/science-environment-46823440

Guardian item on wood burning stoves

bhommels — Fri, 01 Jan 2021 23:08:01 +0000

In our small village, many people have woodburners or fireplaces, meaning I have to turn off my MVHR to avoid it sucking in air that makes the whole place smell like a campfire.
Even with these new standards I expect wood burning to rise to the top spot of domestic pollution generators pretty soon.

Guardian item on wood burning stoves

WillInAberdeen — Fri, 01 Jan 2021 23:59:31 +0000

I was interested by this picture in the government clean air strategy. Wood burning is definitely a problem in the London area, which is well over the WHO target of 10ug/m3. (Don't understand why people burn wood in cities). Other parts of the country are more affected by wind-blown sea salt, such as where we are.

(Edit for clarity: I strongly disapprove of people causing pollution from wood burners, cars, or anything else, but I think the public need to know it's more complicated than blaming just one source for air pollution and so not acting on others)

Guardian item on wood burning stoves

tony — Sat, 02 Jan 2021 08:13:23 +0000

Where are distant upwind vapours coming from, clearly they are massively increased in country

Guardian item on wood burning stoves

WillInAberdeen — Sat, 02 Jan 2021 10:01:45 +0000

Haven't checked their references but I guess sources like deserts, forest fires, crop spraying and industry in central Europe, volcanoes, that kind of stuff.

That graph is a cross section across the UK from Inverness-shire on the left to Kent on the right. SE England has more influence of continental weather and poor air quality, the rest of UK gets more weather off the Atlantic.

Edit: also it's a year round average so won't show up acute problems at certain times of the year like woodsmoke or summer smog.

Guardian item on wood burning stoves

jms452 — Sat, 02 Jan 2021 10:20:49 +0000

Posted By: WillInAberdeenThey could have examined the pros/cons of the upcoming EU 'ecodesignâ€™ smoke reduction standard, supposedly intended to improve on the existing DEFRA smokeless certificates by 80%; or the upcoming ban on under-seasoned firewood and bagged coal; or compared SE England with other parts of UK in terms of smoke and traffic emissions. They could have discussed that a properly insulated house doesn't need a multi-kW room heating stove. They could have discussed that air pollution in the UK is now a small fraction of what it was a few decades ago, a huge success. They could have looked at whether the electric vehicle target will reduce pm2.5 or not. But that would have made their story too complicated!

Indeed! While this release has its 'heart in the right place' i.m.o. there's a distinct lack of big picture consideration here.

How does well seasoned local wood compare to an old oil boiler? What happens when you look beyond direct particulates at the oil extraction (potentially from tarsands), building pipelines/infrastructure (though wilderness), shipping (than rinses it's pollution into the sea) and climate change...

Coal is also relegated to the further down and there's no real differentiation between open-fires and stoves. There's a world of difference between an open coal fire (which is still depressingly common) and a modern wood burner with seasoned wood.

There seems to be the potential here for single issue campaigners to prioritise the local health (of the relatively affluent from a global perspective) over world wide health.

That said I'd agree that those in cities should be doing all they can to avoid burning wood and add in coal, diesel & petrol too.

Guardian item on wood burning stoves

Ed Davies — Sat, 02 Jan 2021 10:20:54 +0000

Posted By: tonyI have been saying this for 25 years, taken a lot of flack over it too.

Yep, but we still get loads of discussion of using wood burners here where, IMHO, it should be considered off topic. I'd agree with WiA that this isn't a great article, it just caught my eye straight after reading a couple of stove threads.

Posted By: tonyWhere are distant upwind vapours coming from, clearly they are massively increased in country

From the end of the BBC article WiA cites:

But one irony: much of the UK's pollution originates in mainland Europe, so we really need neighbouring countries to join the effort.

Of course prevailing winds are in the opposite direction.

Guardian item on wood burning stoves

djh — Sat, 02 Jan 2021 10:44:03 +0000

Posted By: tonyWhere are distant upwind vapours coming from, clearly they are massively increased in country

Good question. Water vapour? What vapours are there that are not organic and also aren't dusts or aerosols etc?
edit: CO2?

What's the big gap in the graph at Edinburgh?

Guardian item on wood burning stoves

WillInAberdeen — Sat, 02 Jan 2021 10:49:11 +0000

Ammonia? NOx?

It's the Firth of Forth.

Guardian item on wood burning stoves

djh — Sat, 02 Jan 2021 11:15:38 +0000

Posted By: WillInAberdeenIt's the Firth of Forth.

Ah, thanks. I had somehow got the idea that graphs were some kind of average perpendicular to the line of transection, but now I see they're just point measurements. I would expect sea salt to be at least as high over the Firth of Forth as it is over the land adjacent?

I haven't found any Imperial source document to back up these graphs. Not giving references should be a crime.

Guardian item on wood burning stoves

Cliff Pope — Sun, 03 Jan 2021 08:39:55 +0000

The Guardian testers must have selected stoves and fireplaces with very poor chimneys.
We don't get a rush of gases into the room when we open the Rayburn door to put more wood on - quite the opposite. The chimney draught sucks in more air.
Likewise anyone who has ever used the newspaper against a shovel trick to get an open fire to go will be aware there is an enormous suction up the chimney. How are the particles supposed to get out into the room?

Or were they testing a flueless woodburner in an open-plan iron age hut with just a hole in the roof to let the smoke out?

Guardian item on wood burning stoves

philedge — Sun, 03 Jan 2021 09:38:27 +0000

Posted By: Cliff PopeThe Guardian testers must have selected stoves and fireplaces with very poor chimneys.
We don't get a rush of gases into the room when we open the Rayburn door to put more wood on - quite the opposite. The chimney draught sucks in more air.

Were the same- open the door or either air control and the fire takes off up the flue like a jet on afterburners. I cant for the life of me see how anything gets out of the fire when its burning. Maybe the problem is with dust from the ash tray??

Guardian item on wood burning stoves

RobL — Sun, 03 Jan 2021 09:47:38 +0000

Posted By: bhommelsg I have to turn off my MVHR

Particulate sensors are pretty cheap now - eg this one seems very capable. Is it worth automating turning mvhr down when the inlet particulates are high ?

https://shop.pimoroni.com/products/pms5003-particulate-matter-sensor-with-cable?variant=29075640352851¤cy=GBP&utm_source=google&utm_medium=cpc&utm_campaign=google+shopping?utm_source=google&utm_medium=surfaces&utm_campaign=shopping&gclid=Cj0KCQiA88X_BRDUARIsACVMYD9CYwTQjfc5yd1r7KKtEQbrFe_pPDGiwMbccDUTr3RPl2pgsF5HIBIaArbkEALw_wcB

Guardian item on wood burning stoves

jms452 — Sun, 03 Jan 2021 09:51:45 +0000

Posted By: Cliff PopeThe Guardian testers must have selected stoves and fireplaces with very poor chimneys.

Presume you mean this article:
https://www.theguardian.com/environment/2020/dec/18/wood-burners-triple-harmful-indoor-air-pollution-study-finds

If so the tripling is quite believable. We sometimes smell wood smoke when refilling a stove (even with a good draw due to turbulence etc.) and that's before you get into starting it and dust burning off on the outside etc.

The things to look deeper at would be the variability of the data (e.g. could it be down to a couple of poor performing stoves?), where the baseline came from and how 'tripling' compares to other sources in indoor air pollution, cooking on gas, frying food, burning a candle...

Guardian item on wood burning stoves

bhommels — Sun, 03 Jan 2021 09:57:02 +0000

Posted By: RobL
Particulate sensors are pretty cheap now - eg this one seems very capable. Is it worth automating turning mvhr down when the inlet particulates are high ?

I was thinking along the same lines, and it would be worth buying one and measuring a few things - you never have too much data!
It is probably the gases that cause some of the "camp fire experience" however, and filters do not help there. Our MVHR has G4 and F7 inlet filters so these should block >70% of PM 2.5.

Guardian item on wood burning stoves

tony — Sun, 03 Jan 2021 11:58:52 +0000

If you can smell it then you have particulates too and the smaller they are the more dangerous.

Guardian item on wood burning stoves

jms452 — Sun, 03 Jan 2021 16:14:48 +0000

Posted By: tonyIf you can smell it then you have particulates too and the smaller they are the more dangerous.

that was my point - i.e. that if you can smell smoke stuff has escaped into the room.

Guardian item on wood burning stoves

WillInAberdeen — Mon, 04 Jan 2021 15:00:47 +0000

Slightly OT sorry, but I found the reduction in pm2.5 emissions in the UK is really impressive and encouraging:

1970: 500 kt/a
2018: 100 kt/a
https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/864778/trends_in_air_emissions_2018.csv/preview

The air is now much cleaner than it used to be, so it's surprising that the press coverage about air quality is mostly pretty negative.

More generally, we tend to hear news reports mostly about environmental doom, and the cost and difficulty of cleaning up, but the tremendous success in cleaning up our air emissions should give people encouragement that we can actually improve on other emissions too. The decarbonisation of electricity is another encouragement.

Guardian item on wood burning stoves

LF — Mon, 04 Jan 2021 15:47:26 +0000

Will,

Is it not smaller particles than PM 2.5 that is the worry. A lot of gaps in knowledge when I last looked into this area. It stopped me looking at gas for cooking long term in the house though.

The government historic data deals with larger particles (PM 2.5 and higher)

Will the removal of these bigger particles (PM 2.5 and above) not mean there are more of these smaller ones. (Less larger particles to interact with and "knock out" the very fine particles. ) ?

Guardian item on wood burning stoves

owlman — Mon, 04 Jan 2021 15:51:28 +0000

What would be interesting Will, would be an international comparison.

Guardian item on wood burning stoves

revor — Mon, 04 Jan 2021 17:03:05 +0000

I wonder if any data been collected on pollution around airports generally, I know Heathrow has been subject to concerns w.r.t the 3rd runway. My wife worked as a Pharmacist in the Manchester area for 35 years and in that time worked in a considerable number of pharmacies around Ringway airport. She would often mention that the pharmacies under the flight path would dispense proportionally a higher number of prescription medications for asthma compared to the surrounding area not directly under the flight path. We lived about 10 mins drive from the terminal and not at all near to the flight path but would very occasionally if the wind was in the right direction smell aviation fuel.

Guardian item on wood burning stoves

Jonti — Mon, 18 Jan 2021 08:46:55 +0000

It seems every so often there will be some article or other about the dangers of wood burning stoves that pops up in the press. Yes, there are problems with burning wood but if the wood is dry (below 20%) and the stove properly installed then maintained the negatives are very much reduced.

The main problem that should be addressed but isn't is not the heat source but rather the need for one. If houses were properly built and maintained then the need for extra heating would be minimal. Of course this would mean proper control of the standard of construction which is not going to happen.

Guardian item on wood burning stoves

fostertom — Mon, 18 Jan 2021 09:15:03 +0000

Posted By: jms452We sometimes smell wood smoke when refilling a stove (even with a good draw due to turbulence etc.)

Lately been lazily lighting using cheap fire lighters. Curious that, ten mins after lighting but not before, when all is blazing and drawing merrily, the stink of paraffin wax in the room.

Guardian item on wood burning stoves

philedge — Mon, 18 Jan 2021 10:05:06 +0000

May not apply to all stoves but with ours theres definitely a right a wrong way to open the doors. Our stove has 2 doors with the outer door closing over the inner door so the inner door is held shut by the outer one. Open the outer door and nothing comes out of the stove so theres no smell when refuelling through just the one door. If we open the second door there is always a puff of smoke as the door is opened. Once its opened the draw up the flue resumes and nothing more spills out, that we can detect!

Guardian item on wood burning stoves

revor — Mon, 18 Jan 2021 10:26:27 +0000

My 2 stoves have ducted air from outside so no draw air from the room. When loading logs after lighting I need to crack open the door first so stove equilibrates the "pressure" to the room otherwise there is a danger of smoke leakage and tiny glowing embers. It only takes a second or 2. It also happens to be what is recommended in the instructions. I believe best efficient combustion takes place at around 15 to 16 % moisture content. Air drying will take moisture down to 15% but one needs to allow 1 year per inch of thickness in a ventilated covered area to achieve this. Moisture meters are cheap enough so no excuse for burning damp wood.

Guardian item on wood burning stoves

bhommels — Mon, 18 Jan 2021 11:20:19 +0000

Posted By: JontiIt seems every so often there will be some article or other about the dangers of wood burning stoves that pops up in the press. Yes, there are problems with burning wood but if the wood is dry (below 20%) and the stove properly installed then maintained the negatives are very much reduced.

Even with the negatives very much reduced, domestic biomass stoves are major polluters as documented here:
https://uk-air.defra.gov.uk/library/reports?report_id=935

Guardian item on wood burning stoves

Simon Still — Mon, 18 Jan 2021 12:00:53 +0000

Posted By: Jonti but if the wood is dry (below 20%) and the stove properly installed then maintained the negatives are very much reduced.

Personally I think there is an issue allowing installation of things that have such a potential for misuse. I'm in London. A neighbour used to collect scrap wood (pallets and the like) from the streets to burn in winter. I've seen people gathering fallen wood on Clapham Common. We sometimes smell woodsmoke thorough our MVHR (not often because the inlets are at ground floor roof level so well below chimneys) but I've also noticed tar like deposits on or wall cappings when cleaning the roof terrace after winter.

Guardian item on wood burning stoves

djh — Mon, 18 Jan 2021 12:03:02 +0000

Posted By: JontiIt seems every so often there will be some article or other about the dangers of wood burning stoves that pops up in the press. Yes, there are problems with burning wood but if the wood is dry (below 20%) and the stove properly installed then maintained the negatives are very much reduced.

That's true but the difficulty is that only using dry unpainted untreated wood relies on all the users choosing to be responsible, and that never happens. Indeed getting all wood stoves propely installed and then maintained has exactly the same difficulty. Some people are good and try to look after the planet; others aren't and don't. Legislation can help sometimes but not everywhere, short of an outright ban.

The main problem that should be addressed but isn't is not the heat source but rather the need for one. If houses were properly built and maintained then the need for extra heating would be minimal. Of course this would mean proper control of the standard of construction which is not going to happen.

Agreed 100%, sadly.