Thinking about a wood burning stove installation? There is a lot to consider. Have a read through the following guide to work out what you need and then use that information to work out roughly what it will cost you under our GUIDE TO STOVE COSTS. Also use our GUIDE TO STOVE QUALITY to familiarise yourself with varying quality of products in the market.
Ring us or call in at our showroom in Rochester, Kent to discuss in more detail.
Who is installing your stove – will you use a HETAS registered installer?
Just as Gas Safe is the governing body for gas installers, HETAS is the governing body for solid fuel installers. All solid fuel installations, including wood burning stoves, must be signed off by a HETAS (or equivalent competent persons scheme) registered installer. Stoves can be installed by non-HETAS registered installers providing your local building control department inspect and certify the works, which will cost approx. £280. NB not all building control departments will certify such works.
As HETAS registered installers we are able to ‘self certify’ and notify your local authority that the works have been completed in a safe and compliant manner without the need for them to inspect. If the installation is not certified by a HETAS registered installer (or building control) the works are deemed illegal and many insurance companies will not pay out on claims for fires caused by incorrectly installed solid fuel appliances. Local authorities can and will fine companies and individuals for illegally installing stoves. To check if a company is HETAS registered go to http://www.hetas.co.uk/find-installer/.
Do you have an existing chimney breast?
Yes: if you have an existing chimney breast it will need to be swept and lined for a solid fuel stove (gas appliance flue linings are not appropriate). Lining the chimney will make the stove operate more efficiently - as the space that needs to be heated up is much smaller if the chimney is lined - and it is also better protection against carbon monoxide gases.
No: If you do not have a chimney breast a ‘twin wall’ chimney can be installed internally or externally – these are large, bright stainless steel chimney structures (but can be factory painted). If they are run internally they can be boxed in.
Distances to combustibles - stoves
Each stove manufacturer will specify the minimum distance each stove must be away from a combustible material, such as a fireplace mantelpiece. plasterboard or timber stud wall. When you are deciding on which stove to install, measure the width and height of your fireplace opening and then check the dimensions against the technical specifications of the stove. Our stoves section gives distances to combustibles for the stoves we supply.
Distances to combustibles - chimneys
The stove pipe must also meet minimum distances to combustible materials. A timber mantel is a common design feature but it must be sufficiently away from the stove pipe (NB it is possible to use fake timber beams that are really convincing - see our installation section).
For internally run twin wall chimney systems there is also a minimum distance to combustible materials, such as a timber floor joist. Better quality flue systems have a distance of 50mm to combustible materials. We only use good quality flue systems that have 50mm distances to combustible materials and 60mm where the flue system offers other qualities such as strong structural support.
What size stove?
The table below will give you a rough guide to calculating the appropriate size stove for your room. You will also need to take into account the age and efficiency saving measures of the house, as older/less efficient houses will require a higher output to heat the room. It is best to have a smaller stove running at full capacity than a large stove running at lower capacity – this makes for greater fuel efficiency and reduces deposit build up in the flueways.
However, while all stoves must give a 'nominal output' for example 5kW or 8kW, all stoves in fact operate between a range of outputs. So a stove with a nominal output of 5kW may have range of output between 3kW and 8kW, depending on how much wood is burning. It is therefore possible to install slightly larger stoves with a nominal output of say 8kW in smaller rooms as the range will be between 5kW and 10kW.
|Approximate age of property|
|Approx size of room: SQM||Period property solid walls, little insulation||1930 to 1950 average insulation||1960 to 1980 average insulation||1990s||After 2000|
|12||Conventional heat requirement kW||2.1||1.8||1.4||1.2||0.9|
|Recommended stove size||2-5kW||2-5kW||2-5kW||2-5kW||2-5kW|
|16||Conventional heat requirement kW||2.8||2.4||1.9||1.5||1.2|
|Recommended stove size||2-5kW||2-5kW||2-5kW||2-5kW||2-5kW|
|20||Conventional heat requirement kW||3.5||3.0||2.4||1.9||1.4|
|Recommended stove size||2-8kW||2-5kW||2-5kW||2-5kW||2-5kW|
|25||Conventional heat requirement kW||4.4||3.7||3.0||2.4||1.8|
|Recommended stove size||2-8kW||2-8kW||2-5kW||2-5kW||2-5kW|
|30||Conventional heat requirement kW||5.3||4.5||3.6||2.9||2.2|
|Recommended stove size||5-8kW||2-8kW||2-8kW||2-5kW||2-5kW|
|36||Conventional heat requirement kW||6.3||5.3||4.2||3.5||2.6|
|Recommended stove size||5-8kW||5-8kW||2-8kW||2-8kW||2-5kW|
|42||Conventional heat requirement kW||7.4||6.2||5.0||4.0||3.0|
|Recommended stove size||5-8kW||5-8kW||2-8kW||2-8kW||2-8kW|
|49||Conventional heat requirement kW||8.6||7.3||5.9||4.7||3.5|
|Recommended stove size||5-8kW||5-8kW||5-8kW||5-8kW||2-8kW|
|64||Conventional heat requirement kW||11.2||9.5||7.7||6.1||4.6|
|Recommended stove size||8-16kW||8-12kW||5-8kW||5-8kW||5-8kW|
|81||Conventional heat requirement kW||14.2||12.0||9.7||7.8||5.8|
|Recommended stove size||8-16kW||8-16kW||8-12kW||5-8kW||5-8kW|
The information in the table is given as a guide and should not be used as a substitute for advice specific to your circumstances.
Do you live in a smoke control area?
Under the Clean Air Act local authorities may declare the whole or part of their district to be a smoke control area. If you live in a smoke control area you cannot burn wood unless you are using a DEFRA exempt appliance. Across North Kent, Maidstone and Swale districts have no smoke control areas while Medway and Gravesham do, but always check.
Does the stove need a ‘constructional’ hearth?
This question is answered by your choice of stove. If the stove can push more than 100°C directly downwards then a constructional hearth is required. A constructional hearth is a solid slab at least 125mm deep (250mm if there are combustible materials underneath the hearth). You may already have a constructional hearth if you have an existing fireplace or a solid floor (i.e. not floorboards). However it must project at least 500mm in front of the fireplace opening, as well as 150mm wider each side, and some existing hearths may fall short.
Many of the better quality stoves do not require a constructional hearth and instead just require a 12mm ‘super-imposed’ non-combustible hearth. Non combustible hearths come in all shapes, sizes and finishes, for example we have a teardrop shaped glass hearth in our showroom. If you have a solid floor (tiles etc) that is at least 12mm thick then your hearth could simply be a change in the colour of the tiles you have. A hearth is there to mark out a safe area around your stove as well as catch any ash or embers that can fall out when you open the door. The third option is to place a decorative barrier around the stove to mark out the hearth area.
Steel or cast – what is the difference?
Most modern British made stoves are steel with a cast door. Jotul stoves are fully cast iron. There are advantages and disadvantages to both:
- Cast iron stoves are comprised of panels bolted together (normally with rope joints) which need remaking every 2-5 years depending on quality and use.
- Cast stoves take longer to heat up but hold their heat, giving an even temperature during operation. Most Jotul stoves have a 20minute heat up time.
- The most controllable stoves are often cast iron.
- Some of the better manufactured stoves, such as Charnwood, have rolled steel bodies so there is no welding at the corners, making them more durable and resistant to damage.
- Cheaper models are welded at the corners.
- Steel stoves heat up the room very quickly, but do not hold their heat as well as cast iron.
What is the ‘Airwash’?
Airwash is achieved by drawing air across the door to create a barrier between the burning fire and the glass. The air is either drawn directly from outside or some of the better quality stoves have developed a design whereby the air is pre-warmed by ducting it around the back and top of the stove before pushing it over the glass. By preheating this air the overall temperature of combustion is increased keeping the door glass cleaner during operation. Many cheaper stoves do not have this facility and the glass will frequently black up.
Do I need ventilation?
Stoves over 5kW output will require additional ventilation. Some stoves have a spigot to connect an external air duct directly to the stove thereby eliminating a cold draught from outside chilling the room.
Wood or Multifuel?
Depending on what fuel you plan to burn, you can buy a wood only stove or a ‘multi-fuel’ stove that will also burn coal based products. The grate is the key. The really well manufactured stoves will have a multi grate that allows you to switch between wood and coal, as each burn differently, in one easy move. Most mutlifuel grates are designed for solid fuel but will burn wood.
Wood moisture content
Dry wood with moisture content <20% is best. More moisture = more smoke + more tar build up in the flue + less efficiency.
Will I save money on my gas bills?
Wood burning stoves are an increasingly popular way of reducing gas bills and using a locally sourced, renewable fuel. Well seasoned, locally sourced wood can cost as little as 1p per kilowatt hour (kWh) and many people can source it for free. Mains gas is around 4.8p per kWh (source: www.confusedaboutenergy.co.uk). A 5kW stove that is used for 4 hours most days in winter would save around £155 per annum, assuming the wood is purchased. An 8kW stove used for 5 hours per day would save £350 per annum.