Firewood & wood burning stoves

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1 Firewood & wood burning stoves Lightfoot is a charity based in Bishops Castle. Its aim is to help you to understand how you use energy and to help you identify where you can save money. Lightfoot provides services which people take steps to: Reduce energy bills Reduce wasted energy Reduce CO2 emissions A practical guide for domestic stove users. Lightfoot gives sensible advice, guidance, information, support and practical help, throughout and Mid Wales. A Welsh version of this guide is available to download on the Lightfoot Website.

2 Firewood & wood burning stoves A practical guide for domestic stove users. These leaflets have been developed to help stove users and to promote sustainable use of woodlands as wood fuel. This information is supported by Environment Wales with funding from the Welsh Assembly Government which is focused on finding ways of living more sustainably.

3 10 Tips on Running a Woodfuel Stove 1. Burn only seasoned wood Wood should be cut, split (to 100 to 120mm or 4 to 4.75in diameter). Stack to dry until the moisture content of 25% or less, ideally less than 20%. Burning wet wood will produce tar deposits and will not give an efficient heat output leading to chimney fires. Try to have some logs stored in the house to dry out further. 2. Store your wood correctly and use a Moisture Meter Store your wood in a well ventilated woodstore and position it on a South or South East facing wall. Do not store in a closed shed. A moisture meter can be used to test how dry your wood is when buying and before burning 3. Lighting your stove Be prepared and have a store of dry kindling and newspaper available near your stove (softwood such as pine or spruce are good for this) Light at the base of the fire and open all air vents and reduce the air accordingly as the wood starts to combust until finally the stove is up to running temperature (see manufacturers guidance) 4. Use a Stove Thermometer Most stoves need to be burning at a certain temperature to burn the fuel efficiently (approx. 260 C/500 F) Thermometers are relatively cheap and a useful guide to efficient wood burning. 6. Firewood burns best on a bed of ash Never clean out your stove completely of ash, instead just remove the ash box below and empty that only. 7. Understand your stove Find out how your air vent controls work; get an operating manual for your stove if you haven't already. 8. Do not overfill your stove with logs And make sure there is good spacing between the logs; this will help to burn the logs consistently and get more energy from the combustion. 9. Overnight burning Fully load the stove with well seasoned wood until the load is well alight then close down but leave the secondary air vent open about 8 to 10mm. Unless the logs are well seasoned avoid overnight burning as it leads to tarring of the flue. Always have a good supply of kindling at hand in the morning to relight. Try using wood briquettes as an alternative to coal. 10. Flue Maintenance A flue should be swept at least once a year, if you use your stove daily then twice a year is advisable; stove efficiency is dependent on its draw so the flue must be clear of deposits which is also a chimney fire risk. 5. Do not slumber burn There should generally be visible flames in the firebox the firebox should look clean, white-ish firebrick and the glass on most stoves should be clear if this is not happening then your wood is not dry enough or the fire is not up to the right temperature before closing down the air flow.

4 Buying a Stove and Installation There are a few questions that you should ask yourself: Your Budget How much are you willing to spend usually the more expensive, the better quality, efficiency and design. Visit a supplier. Although you can buy some of these stoves a little cheaper on the net, the advice you get from a shop is invaluable and the follow up service doubly so. Reasons to install stove correctly: Flue gases may leak into the home through gaps inside the chimney The gases will tar up the inside of the chimney leaching into masonry and cause damage The tarring can catch fire and cause a chimney/house fire Increased burning efficiency The better flue fittings will be lined with perlite or vermiculite (or similar) to insulate the flue. This reduces gas and tar seepage if there is a hole in the flue. Other cost factors to consider: What is the size of the room you wish to put it in? Is there an existing fireplace if not, it will cost more. What size is the hearth? Are you intending to heat just the room or beyond? you can always leave the door open to heat other parts of the house or fit a back boiler to take some heat to your hot water tank Before you buy ask yourself: Why do you want a stove? Do you have room for wood storage? What do expect from your stove? Do you have an idea what stove you would like? Stove and Flue Installation Installing a flue is advisable and a recommended industry guideline. Fitting a flue is sometimes a home insurance condition. Fit a stove and flue properly for safety reasons. Installers should be accredited by HETAS

5 How to Buy Firewood There can be a huge variation in the type of firewood available and its quality. When buying wood you are completely within your right to know what you are buying. It may be a difficult conversation to have to get the best deal for you. Quality: The most important thing to consider when purchasing is how dry is the wood. This is the crucial aspect of getting the best efficiency out of your stove. Wood should be seasoned to below 25% moisture content before burning. Ask the supplier before delivery whether the firewood is freshly cut, part-seasoned or seasoned. There should be a price difference for each of these. In fairness, some suppliers may not be fully aware of moisture content, appropriate storage and seasoning, but a decent supplier should know about these factors and no excuses should be acceptable it s their job description to know! There are plenty of good reputable suppliers out there and Woodfuel Wales have an online directory of suppliers registered with the Quality Assured Fuel scheme or visit the Lightfoot website for local suppliers in the Marches. It is always best to shop around. Quantity: Always try to buy the firewood by volume - buying by weight is not advisable if you do not know the moisture content of the logs. Try to buy in loose cubic metres - when a supplier says they sell by the load, trailer or bag then ask what size it is - it takes just a few seconds to measure up. If you are buying in volume softwood should always be considered cheaper due to the lower density. Moisture Testing: When the delivery arrives make an inspection before the load is tipped. It is not easy to visually assess the moisture content of firewood, so use a moisture meter. This can measure the average water content in the logs. Moisture meters are relatively cheap and cost efficient when buying from non-accredited sources. Please see Lightfoot website or leaflet on how to correctly test firewood. Size: When you order your wood you need to specify the length of the log to meet your requirements, i.e. the size of your stove doorway. An important factor for efficient burning is the diameter of a log. A log that is split to mm in diameter (3.75 to 4.75 inches) dries quicker and burns more efficiently. Type: All types of wood have approximately the same calorific value per kilogram. Historically, hardwood is thought to a better firewood, however all wood is good as a fuel by weight. Density of the wood plays a role in the burn time. You will get longer burn times from hardwoods such as Oak, Beech, Ash etc. If you require heat quickly then softwoods such as pine, spruce, willow or popular are very good for this. Beware of variable sizes of builders bags, sand bags, trailers etc. If the supplier doesn t know the size and is not prepared to measure up find another supplier.

6 Seasoning Firewood There are two significant factors that affect the energy you get from wood: Moisture content - Water present in the firewood Density of the wood - hard wood gives a longer and more consistent burn, softwoods gives out heat quicker but last a shorter time. There are many myths about what wood you can burn. However the best principle is Wood should always be seasoned before burning. What is seasoned wood? The recognised standard for seasoned firewood is moisture content at 25% or below. However, for best results burn at 20% moisture content or below. The only way to really know is to use a moisture meter - see the Lightfoot website for more details. More cost effective If the wood is wet then heat is lost boiling off the moisture reducing the heat to the room. Using wet wood means you have to burn larger amounts of wood for your heating requirements Seasoning: doing it yourself Correctly storing your wood is the key to getting good quality dry firewood. A purpose-made woodstore This should be: covered from the rain and allows free flowing air to enable the drying process The woodstore should be raised off the ground. Slated sides with gaps are acceptable but a closed shed will not work (it will not dry properly and can become mouldy which draws more moisture in and becomes poor wood for burning) Log Size Chop to around 100 to 120mm (4 to 4.75 inch) diameter Splitting wood to this size is best for the drying process and efficient burning Positioning Position the woodstore in sunny but dry position South to SE is best. Avoid South West due to prevailing weather (rain) and Northwards due to lack of sun The benefits Burning dry wood will result in: Less tarring of the flue Reduces risk of chimney fires Better efficient burn warmer house

7 How to Use a Moisture Meter How to use a Moisture Meter Moisture meters can be used in various ways for woodstove use. They are often used for those people who are cutting and seasoning their own wood. But more importantly they can be used to check the quality of wood bought from suppliers and make judgements on when firewood is ready for burning. Remember: Seasoned firewood should have a moisture content of 25% or less. If you can store firewood to 15% this would be an ideal world scenario. There are various meters available and at alarmingly different prices. However, for small domestic use it is advisable not spend more than 30. Most moisture meters have instructions included and these should be followed. The basic process of finding out the moisture content of logs is as follows: Take a random selection of around 3-4 logs per cubic metre (m2) per load. Split each log down the middle In the centre of log push pins of meter - three measurements are taken on the freshly split surface: 5cm in from each end of the log and in the middle of the split surface with sufficient contact (see figures). Do this to all the logs and take an average of the readings (this will be only an approximate indication).

8 Why Wood Burning Stoves? Wood is a great way to heat your home Modern wood burning stoves are very efficient With up to 90% efficiency, such good combustion technologies, this makes Woodfuel one of the cleanest heating sources. Woodfuel is a cheap source of domestic heating. Using Woodfuel heating can reduce fuel bills. Typically, in 2013 the cost of domestic heating is as follows: woodlogs at 3 pence per KWt hour Oil at 8p per KWt hour coal at 9p per KWt hour Electric (day rate) 13p per KWt hour Wood is a sustainable fuel CO2 emissions are very low so long as forests are sustainably managed woodfuel provides a renewable source of energy. The UK has a regulated market so nearly all Woodfuel is considered sustainable if from UK provenance. Woodfuel use can be good for wildlife Using wood to burn can bring benefits such as bringing woodlands back into active management. Managing forests for woodfuel can be very beneficial for wildlife. Sustainable Jobs The use of wood for fuel promotes Woodfuel businesses, creating sustainable long term jobs in the countryside. These financial benefits can help rural community resilience.