Should I choose a multi-fuel or wood stove?
In short, if you want to burn solid fuel (coal) you definitely need a multi-fuel stove. If you want to burn wood you can choose either, but dedicated wood burning stoves will usually give you more space to burn larger cuts of wood.
Wood burns best from the top downwards on a thick bed of ash. Therefore, wood burning stoves will have no grate or ash pan. The wood is burned flat on the base of the stove and the ash is allowed to build up. When too much ash has accumulated you scoop some out, but it’s best to always leave a good bed of ash. If you are burning dry wood in an efficient stove, and burning it well, then very little ash should be produced. The only time you may need to empty out all of the ash is if your chimney sweep asks you to.
To burn solid fuel, a multi-fuel stove with a grate and ash pan is needed. Multi-fuel means the stove is capable of burning both solid fuel and wood. Solid fuel burns more fiercely than wood and produces more ash. To avoid the ash clogging the fire and restricting the supply of oxygen, a grate is needed for the ash to drop through and into an ash pan. It then needs to be cleaned out regularly. Some multi-fuel stoves, have a grate with moveable bars, known as a riddling grate, to help you push the ash through.
Which size stove should I choose?
There is a calculation you can use based on the dimensions of the room, which will give you a good idea of the heat in kWs needed for the space. See below. This won’t take in to account several other important factors though. How well insulated is the room? Is there a staircase? Do you always leave doors open to other rooms? All these are taken into consideration by our surveyors when they come to quote for installation. They can then give a recommendation based on many years of experience!
Measure your room in metres. Multiply the length, width and height. Divide this by 14. You will then have the number of kWs needed.
(Length x Width x Height in metres) ÷ 14 = kWs
It is important not to choose a stove with an output far above what the room requires. If you try to burn a large stove under capacity, the gases aren’t burnt off quickly enough and the chimney tars up. The air wash system, to keep the glass clear, also won’t work well. If you choose a stove which is too small and regularly fire it over capacity you run the risk of damaging the stove.
Do I need a lined chimney?
Stoves should ideally be fitted to a 6″ lined chimney. (Occasionally a large stove will have a 7″ flue spigot and require a 7” chimney). This is not a legal requirement but is highly recommended.
The efficiency levels which make wood stoves so much more practical, kinder to the environment and cheaper to run are determined during testing on 6″ wide chimneys. You will not be getting the best out of your stove without one.
When a stove is fitted to a larger chimney there may be problems controlling the fire. On still days the chimney might not draw the smoke up properly, making it harder to maintain a good fire and producing more tar. On particularly windy days the chimney may draw too much, so that it’s difficult to control how fast the fire burns.
The warmer the chimney, the better the draw. The flexible stainless steel liners we use are insulated so that heat is retained. This is particularly important when installing highly efficient stoves that allow less heat to be lost up the chimney.
In older chimneys there may be concerns over the condition of the brickwork. It would be a considerable safety concern if fumes were to leak out into upstairs rooms. Stoves produce far more Carbon Monoxide than open fires.
It may be that your chimney is already suitably lined. If your chimney was built after 1966 it should have been built with some form of liner to meet building regulations. For the purposes of a stove this should ideally be 6″ wide. If the chimney is quite a bit wider it may be advisable to re-line.
There are many different methods and materials and all have their uses, advantages and disadvantages.
We usually install flexible twin wall stainless steel liners. . The liners can also sometimes withstand a chimney fire, and are easily and quickly removed if they need to be replaced after a fire. They are most commonly used for multi-fuel and wood stoves.
Do I need an air vent in the room?
Multi-fuel and wood burning stoves pull in air from the room to allow them to work. If the stove is over 5kW you do need an air vent in the room. In modern, airtight, houses an air vent should be installed whatever the stove’s output.
Some stoves can have an external air vent fitted. The air is then drawn in from outside directly into the stove, bypassing the need to have an air vent in the room which could create draughts, and keeping a modern house airtight.
I don’t have a chimney, can I still install a wood stove?
Yes, a chimney can be created for you.
A solid insulated twin wall stainless steel flue can be erected inside or outside your building and can be used for any appliance or fuel. With an inch of mineral insulation, tar will not be a problem if dry wood is burned.
The flue can either be stainless steel or have a black coating. Most often, we install stainless steel twin wall flues. Customers often expect these to be intrusive, but as they reflect the colours around them, they tend to sit better in their surroundings than the black coated option.
It is particularly important to have a site survey if you’re considering a twin wall flue. Internally, you need to make sure that there is enough space to install a stove, hearth and twin wall, and maintain a suitable distance from combustible materials. Externally, the twin wall flue needs to be a certain height, and a suitable distance away from taller buildings. This needs to be considered particularly when installing a twin wall system in a single storey extension to a two storey building.
Contemporary wood stoves, or stoves with store stands to give them more height, can look fantastic on their own against a wall. However, if you prefer a more traditional look and have the space to install a fireplace.
Why should I use a HETAS registered installer?
Stove installations must be registered with the local authority, whoever they are installed by. HETAS are the official body recognised by the Government to approve and register competent installers of wood and solid fuel appliances. Just as ‘Gas Safe’ (and previously CORGI) are for gas installers.
It really is vital to be able to prove that your stove installation is safe. If you should ever have a chimney fire, your insurance company will need to see that the stove had been installed correctly and certified as a safe installation. If you sell the property in the future it’s also likely that you’ll be asked for a HETAS certificate.
Using a HETAS registered installer gives you the peace of mind of knowing that your stove has been installed safely by an experienced fitter. We register the appliance with HETAS online, it then gets sent to you direct in the post this can take 3-4 weeks to arrive.
If you use someone who is not registered to install the stove, you need to inform the local authority yourselves. They will then charge to come out and certify the installation. Of course, at that point, the liner has already been installed and hidden away inside your chimney, and it isn’t possible for them to know that it has been installed correctly. We’ve been asked to rectify enough poorly fitted liners to know that builders and DIYers often get it wrong.