A few solid fuel stoves are available which are only able to burn wood: some have the option of being converted to burn coal: and others are supplied ready to burn either fuel as standard. To burn coal, a grate and some means of removing ash (usually an ash pan) are required. Such a dual-fuel appliance is known as a “multifuel” stove.
Yes. The chimney is in effect both chimney pipe and engine for your stove. It needs to terminate in clear air and provide the necessary draught. It should be well insulated to keep flue temperatures above the dew point, but engineered to cope with abuse. Please ask for our advice and feel free to show us your plans before you build.
The chimney can be of traditional brick or stone construction, lined with clay, refractory concrete or pumice flue liners. It should be remembered that a traditional chimney stack requires a proper foundation; thus whilst it will almost always be the most appropriate choice for new build, blending in with the rest of the building materials, it is usually the most expensive option if one is adding a chimney onto an existing property.
Less expensive options include several proprietary prefabricated block chimney systems such as Isokern DM, with one block stacked one on top of the next Lego-fashion. However, the most frequently-used method for providing a new chimney is to use a prefabricated twin-wall insulated stainless steel system such as Chimaster MF or Selkirk Metalbestos SM. These chimneys can usually be installed either up inside the building, or externally fixed to the outside wall.
On 1 April 2002 the law changed with the revision of Section J of the Building Regulations, and the introduction of a revised Approved Document J (AD.J) providing guidance on how one may comply with the regulations. A copy is available to read in our showroom on request, and at your local authority offices. If you have internet access, you may download AD.J in Adobe Acrobat .pdf format from www.planning.dtlr.gov.uk/advice.htm. The document can also be downloaded from our own home page at www.woodburners.com.
Under the new regulations work on fireplaces, hearths, flues and chimneys, and the installation of woodburning or multifuel stoves are all controlled building operations. Unless the work is carried out by an approved installer such as ourselves under the HETAS ‘Competent Persons’ scheme, customers are advised that an application should be made to Building Control prior to the work being carried out.
In new build, Building Regulations require the installation of suitable Class 1 liners in a masonry chimney. These are usually composed either of clay, refractory concrete or pumice.
Before installing a stove into an existing unlined chimney, it should be inspected by a Competent Person to determine whether it is safe to use without a liner. Older chimneys generally require lining and insulating, and the material used should be appropriate for the appliance being fitted. It is for instance both dangerous and illegal to connect a light duty flexible gas liner to a solid fuel appliance. The appropriate diameter liner should also be used, both to achieve the correct chimney draught, and to ensure that all the products of combustion are safely evacuated.
The material most commonly used for retrospective lining is stainless steel. Where an existing flue is perfectly straight, rigid sections of fluepipe can be used: but where there are bends in the brick flue, a flexible liner is usually more appropriate. This is available in two grades of stainless steel: 316 and 904L, the latter being substantially more corrosion-resistant. The liner is normally surrounded with an insulating material -- most commonly “Leca” (small beads of lightweight expanded clay aggregate), or mineral fibre such as Rockwool or Gypglas. It is important that a practical cleaning access is provided to facilitate regularly chimney sweeping. Any visible stainless steel is usually sprayed with high temperature paint to match the stove.
Yes. With an insulated liner installed, flue deposits should be much less than without one: but regularly annual or semi-annual sweeping not only keeps the liner clean, but confirms that dangerous tarry deposits which might result in a chimney fire are not being formed. Regular sweeping is your best insurance policy against chimney fires, and knowing it is clean provides peace of mind.
Based on a typical overall chimney height of 24 feet, the materials cost is likely to be approximately £600 to £800 including VAT, depending on the grade of the stainless steel liner used (a liner suitable for burning both wood and solid fuels is more expensive than a liner for burning wood alone). When lining a large chimney such as an inglenook, there is also an additional £200 or so for high temperature Rockwool insulation compared to the Leca infill used to insulate smaller flues. The cost for installation labour for a liner and insulation is usually about £480 in the New Forest area, but would probably be more if any building work is also involved such as opening up an original fireplace recess, installing a lintel or beam, laying or extending a hearth, building a new surround, etc.
Every installation is different, and individual requirements for fluepipe therefore vary considerably. For this reason, flue materials are never included in the basic price of the stove, but are supplied as necessary for each situation.
In front of the chimney breast a ‘constructional hearth’ at least 500mm (20”) from front to back is required. Where there is a concrete floor slab, this is usually sufficient; but with a suspended wooden floor, the floorboards / joists must be cut back and concrete used to build up a constructional hearth, usually from ground level. The ‘finish hearth’ is then laid on top of this using tiles, bricks, granite or marble; this finish hearth must extend at least 300mm in front of an open fire or a stove which has doors which can be opened, and at least 150mm on each side.
Where there is no chimney breast, a freestanding constructional hearth must have dimensions of at least 840 x 840mm. A new relaxation to the regulations allows the constructional hearth to be dispensed with and a minimum 12mm thickness of non-combustible material to be laid over a wooden floor where the temperature under the stove never exceeds 100 degrees C during normal operation.
With sealed gas stoves, 225mm of hearth is required in front of the appliance unless the firebed is at least 225mm above the floor covering.
Some people have distant childhood memories, or perhaps more recent personal experience, of an open fireplace which was notoriously difficult to light. A modern stove is in fact very easy and quick to get going, and the best materials are freely available: balled-up sheets of yesterday’s newspaper, pieces of cardboard, and a few handfuls of dry kindling wood. One match should be all that is needed, and within a couple of minutes the fire is roaring away and small logs can be added.
The cardinal rule is this: whatever type of wood you burn -- be it softwoods such as pine or larch, or hardwoods like oak and beech -- it is the dryness of the wood which is by far the most important factor. Wood with a high moisture content will be much more difficult to light: once alight, it will provide little useful heat because most of its latent energy is being used to drive off the moisture as steam: and the risk of cool moisture-laden flue gases condensing in the chimney are greatly increased. Such condensates are potentially dangerous if they catch fire, and are very likely to produce tarry stains and smells if they seep through the chimney brickwork.
Wood must be “seasoned” for at least one summer before being burnt -- and seasoning for two summers is preferable. To season wood properly, pieces which are too long need to be sawn to stove length and tree trunk ‘rounds’ need to be split. The wood then requires maximum exposure to sun and wind: the sunnier and draughtier the position of the woodpile, the better. The top should be covered to stop rain soaking down through the pile, and logs should be stacked with gaps to allow air movement. Storing unseasoned wood in the garage or in a closed shed is not recommended: it will not be able to dry out easily, and wet timber will just encourage rot and the growth of fungi.
About twenty years ago, prompted by the 1970’s oil crisis and the rapid spread of Dutch elm disease, interest in woodburning stoves really started to take off in Britain. Partly due to the recession which was occurring at the same time, many small workshops up and down the country, recognising the growing popularity of imported stoves, started to build and market what unfortunately proved to be rather poorly-designed lightweight steel designs. Compared with the high quality (but expensive) cast iron stoves then being imported from Scandinavia, Europe and North America -- manufactured by companies with many years experience of stove design -- it was a fair observation at the time that “cast iron was better than steel”.
However, during the late 1980's and 1990's the British stove industry has finally come of age, and we believe that some of the best and most efficient designs available anywhere are now built in this country from laser-cut fabricated steel plate. The biggest advances in recent years have been in combustion efficiency, and this has directly contributed to the ability of some stoves to keep their glass door panels almost completely clean.
There are two basic designs of stove: the “inset convector”, and the “freestanding” stove. Inset stoves are designed to be ‘built in’ using brick, stone, granite, marble or some similar non-combustible material, and they incorporate internal air channels and heat exchangers to transfer heat into the room by convection. So long as the fireplace recess is marginally larger than the dimensions of the stove firebox, such a stove can usually be built into an existing or specially prepared opening.
Freestanding stoves, however, are designed to have air circulating all around them, and it is especially important that there is as much space above a stove as possible, with the ideal being something between 12” and 18”. A minimum of about 4” on either side and 2” behind should also be allowed. Where the space above the stove would have to be much less than 12”, it would be better either to position it in front of the opening, or at least half in and half out (but always remembering the building regulation requirement for the minimum 300mm hearth extending in front of the stove).
The answer is yes -- most stoves can have an optional boiler fitted inside, capable of heating domestic hot water and a towel rail. Some larger stoves can be fitted with much more powerful boilers, capable of heating six or more radiators as well as providing hot water. It is even possible to “interlink” a woodstove into a conventional gas or oil-fired central heating system, although you should seek specialist advice before attempting this.
When a boiler is fitted into a stove, the more powerful the boiler, the less direct radiant heat is emitted into the room. It is therefore very important to first work out how much direct space-heating is needed, before deciding which stove and boiler combination would be appropriate.
The larger the room or the area requiring direct space-heating from the stove, the less economic it is likely to be to run radiators: if all the warm air produced can be encouraged to spread around the house by natural air movement (for instance, an open staircase allows heat to rise upstairs), or possibly by employing an extract fan, the need to use radiators to accomplish the same job is reduced. Generally speaking and for most lifestyles, it is advisable to have a conventional central heating system working in the background, with thermostatic radiator valves fitted. The woodstove will then contribute its heat output as space heating, and when a particular room reaches its pre-set temperature, the radiator in that room will turn itself off automatically, thus reducing the total heating load on the conventional boiler and saving fuel.
Tar is one of the visible products of prolonged wood fuel abuse, and is avoidable; very few of our original customers have a problem.
We stock a variety of preventative, monitoring, containment and removal aids to increase safety margins and reduce fire brigade-dependency. Aids include “Heatabix”, stove thermometers, chemicals, brushes and rods, etc. Dirty smoke emission from the chimney pot is a sure sign of incomplete combustion and should be minimised. And always remember the maxim, “A clean chimney never caught fire.”
For most makes of multifuel stove, and especially where infrequent stoking is required, we would advise using Chinacite or German Anthracite (rather than Welsh). Some manufacturers also recommend certain proprietary fuels including Sunbrite and Homefire. Coalite and ordinary house coal are not recommended. With Clearview Stoves, which are unusually efficient, the best value may be obtained by burning Columbian Group 2 house coal. This fuel does however produce more ash and clinker than Chinacite, and requires more frequent stoking.
Yes -- you can quickly and easily make your stove look like new by using a specialist high temperature aerosol paint. We can also supply a special glass cleaner for sooty doors, new ceramic door panels in case you accidentally break one, and replacement gasket material and high temperature adhesive for renewing door seals when required (an easy DIY job.)
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If we run our stove hot, it’ll burn up the lot, it’s safe, and cosy, and clean;
If they smoulder it cold, it’s got to be told, it’s dangerous, dirty, and mean.
Too much of a belt, and a stove might just melt – and that’s not really our scene.
Copyright 1999 New Forest Woodburning Centre, The Old School, Church Lane, Sway, Hampshire SO41 6AD
Tel. (01590) 683585
Fax (01590) 683587