House coal and damp wood to be banned by 2023 to reduce pollution levels

The sale of the most polluting fuels burned in household stoves and open fires will be phased out from next year to clean up the air, the government has said.

Plans to phase out the sale of house coal and wet wood have been confirmed as part of efforts to tackle tiny particle pollutants known as PM2.5, which can penetrate deep into lungs and the blood and cause serious health problems.

Wood burning stoves and coal fires are the single largest source of PM2.5, contributing three times as much of the pollution as road transport, the Department for Environment, Food and Rural Affairs (Defra) said.

These produce less smoke and pollution, and are cheaper and more efficient to burn, officials said.

“By moving towards the use of cleaner fuels such as dry wood we can all play a part in improving the health of millions of people. This is the latest step in delivering on the challenge we set ourselves in our world-leading clean air strategy.

“We will continue to be ambitious and innovative in tackling air pollution from all sources as we work towards our goal to halve the harm to human health from air pollution by 2030.”

Sales of all bagged traditional house coal will be phased out by February 2021, and the sale of loose coal direct to customers via approved coal merchants will end by February 2023.

Sales of wet wood in units of under two cubic metres will be restricted from February 2021, to allow for existing stocks to be used up.

Wet wood sold in larger volumes will need to be sold with advice on how to dry it before burning from this date, the government said.

Manufacturers of solid fuels will also need to show they have a very low sulphur content and only emit a small amount of smoke.

Prof Stephen Holgate, special adviser on air quality at the Royal College of Physicians, said: “We know that air pollution causes significant health issues across the life course. It is key that the government does everything it can to improve the air we all breathe. Today’s announcement on domestic burning is a welcome step forward, and will in time, play a role in reducing the pollution associated with PM2.5.

“Inhaling combustion particles from any source is harmful, but more so than ever when it’s directly within your home. Burning coal for heat and power has to stop and strong guidance is needed to insist that if wood is burnt in approved stoves, it is non-contaminated and dry.”

John Maingay of the British Heart Foundation said: “Wood and coal burning accounts for 40% of harmful levels of background PM2.5 in the UK, and our research has shown that toxic PM2.5 can enter the bloodstream and damage our heart and circulatory system.

Tips for efficient log burning


The wood is utilised in the best way when the draught control is fully open and the flames are intense. That will also reduce pollution, because gas particles are combusted and produce heat instead. Once your home is warm, the temperature is regulated by the amount of wood, not the air control.

Small amounts of smoke is a good sign

You want a minimal amount of smoke coming from your chimney. Smoke is not “exhaust” – it contains high energy gases that were not burned. That’s why it is a good idea to go outside and take a look at the smoke from the chimney. Dense, black smoke is a sign that the combustion is not optimal, usually because the fire in the wood stove is not intense enough. When the wood stove burns optimally, only a bit of steam and some light, odour-free smoke escapes from the chimney.

A clean wood stove is a warm wood stove

Remove soot from your wood stove and the flue pipe once a year. That way, your wood stove will get warmer. A soot layer of even a few millimeters reduces the effect because the heat is not conducted so well, but will go up and out the chimney. Clean it more often if you burn a lot of pine wood which leaves more soot than other types of wood.

Different types of wood provide different levels of heat

Hardwoods provide more heat than softwoods with the same volume, but per kilogram, the different wood types will give off the same heat, and softwoods are often cheaper to buy. Softwoods are the perfect firewood at the start and end of the winter when it is less cold. They provide a cleaner burn without making the house into a sauna. It will burn quicker, but it can be extended by burning with a hardwood log.

Overnight heating

Very few wood stoves can burn longer than two to three hours on one wood load. The old way of closing the air supply so that the coals will smoulder overnight is a source of pollution and creates the risk of a chimney fire. In addition, the heat benefit is poor as the gases are not combusted and the energy is not utilised. The last wood load in the evening should be some bigger hardwood logs that burn as normal with the air vents open. Even if the fire dies out, the insulation in the house will keep the heat in. The stove and chimney will still be warm in the morning and it is no problem to get the fire going again.

Turbulence helps

Turbulence is important when lighting the fire because when the temperature is low, the oxygen does not mix with the molecules in the wood. Swirls of air bombard the smoke gases with oxygen and makes the lighting easier. This is the reason why the firewood catches fire more easily when the door to the wood stove is left ajar. Some houses are so sealed with insulation that you should open a window when lighting the fire. A blow pipe is also an excellent aid to get the fire going, much more so than bellows.

Lighting from the top is better

Many of the modern wood stoves were designed to burn from the top down. Take a look at the user manual or get a new one from the Internet if you burned it. Lighting from the top down is done by stacking logs of wood quite tight and then lighting a small fire on top of the wood so that the fire burns downward. The wood stove will reach its operating temperature quicker, the gases will burn better and the wood load will last longer.

Always more than one log

You should always put two or three logs on the fire at a time – one log on its own will often die out. The reason is that the burning of a log happens in three stages, and one single log is not able to keep its own process going. More logs have a bigger surface, creates more turbulence and keeps the burning process going.

Carnethy Woodfuel primary hardwood species

All our hardwood logs are sourced locally from Edinburgh, the Lothians and Borders and are seasoned for at least 12 months and sold with an average moisture content of 22%. We have chosen to sell hardwood logs only based on their excellent burning efficiency and heat output.

Our supply of wood has been sourced responsibly and is obtained primarily from dead or dangerous trees that require felling.

Hardwoods are generally better for burning than softwoods. As a rule of thumb hardwoods are produced by slow-growing deciduous trees and therefore the logs have a greater density than the faster growing softwoods from evergreen trees.

In summary, hardwoods tend to have broad leaves, while softwoods tend to have needles and cones.

As a rule of thumb, wood which is well seasoned makes a distinctive ‘clack’ rather than a dull ‘thud’ when knocked together. It will also feel much lighter than an unseasoned log.

Other indicators of a seasoned log include the bark peeling away and cracking and splitting of the wood around the outside. It should be stacked off the ground with plenty of space between the logs to allow air movement and with the top covered to keep rain and snow out.

Seasoned wood should give you approximately 50% more heat than the equivalent unseasoned log.

Our hardwood logs that make up our bulk bags generally contain the following mixed species:

1. Beech

This makes a great well burning log although it does contain a high water content and can take longer to season than some other log varieties. Beech rarely throws sparks and makes good embers. Beech trees grow in a variety of different soil types and can grow up to 100 feet tall.  A mature beech tree develops a huge canopy which carpets the forest in a dense shade making it difficult for other seedlings to grow.

2. Birch

These logs burn fairly quickly but provide a good heat output, bright lively flames and a pleasant smell. Birch are usually small to medium sized trees that grow in lowland areas and have shallow root systems. These trees are probably best known for their unique bark

3. Sycamore

This common European tree makes a great wood burning log with a moderate heat output and good flame.

4. Oak

Generally considered one of the best hardwood logs which burns slowly and produces an excellent heat. The oak species consists of about 600 different types and can live for 200 years and grow as tall as 100 feet. The fruit of the oak tree is called the acorn. The trees start producing acorns when they are 20 years old. By the time the tree reaches 70-80 years old, the tree will be producing thousands of acorns

5. Rowan.

This tree produces lovely red berries in the Autumn producing slow well burning logs.

6. Ash.

Widely regarded as the most efficient burning wood type, with low smoke and an excellent flame pattern providing plenty of heat and little residue. A freshly cut piece of ash has a moisture content only slightly higher than seasoned ash.  This allows the ash tree to be safely used immediately after harvesting.

Never use wet or unseasoned (green) wood as this will cause a lot of smoke and a very disappointing fire. It could quickly result in the build up of soot and creosote which could easily cause a chimney fire.

Burning wet or unseasoned wood will also reduce the effectiveness of a wood burning stove and very likely to result in a staining and blackening of the glass.