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Choosing Your Stove

In England and Wales, there are only two routes to legally install a domestic solid fuel, wood or biomass burning appliance.

  • Use a registered installer who can self certify that the work he does complies with the relevant Building Regulations; or

  • The consumer applies to their local authority building control department for a building notice BEFORE work commences, and pays the appropriate fee (possibly up to £300). 

It is generally much simpler and cheaper to use an HETAS registered installer who will leave you with a Certificate of Compliance as a record of the job and that it complies with Building Regulations. A copy of the certificate is forwarded to HETAS who notify the local authority on your behalf.

HETAS is the official body recognised by government to approve solid fuel domestic heating appliances, fuels and services.  We are an approved HETAS retailer and installer, visit the HETAS website for information and free advice sheets

This guide, the information from our brochures, and our expert staff will assist you in selecting the ideal stove for your needs and the most practical for your home. Always feel free to ask, we have been here since 1961 and are experts in our field. We can help you to reach the right decision for you as an individual.

The information in this guide is JUST a guide. Do not be tempted to fit a stove into an unsuitable fireplace. Installation must be carried out in accordance with building regulations, although ultimately manufacturers instructions take precedence and should be used as reference material.

Document J of the Building Regulations states that any work which affects an existing chimney (i.e. fitting a new stove or liner) or creating a new chimney now comes under Building Control.

Download Document J now

What is the right size stove for you?

Clearances for solid fuel stoves

Hearths in general

Hearth Sizes & Thickness

Hearths for freestanding stoves

Chimney Liners

Multifuel Vs Wood Burning Stoves

What Next?

What is the right size of stove for you?

The recommended heat output depends on your room size, and the level of insulation you have:

  • Classic buildings require 1Kw of heat output per 14 metres cubed

  • New builds require 1Kw of heat output per 21 metres cubed

 

To work out the Kw output needed for your room, calculate the volume of the room space:

 LENGTH x WIDTH x HEIGHT  (in metres)

 divide this by either 14 or 21

e.g. 4m x 5m x 2.5m = 50m³ 

An older property would be 50m³  / 14 = 3.57Kw

A new build would be 50m³ / 21 = 2.36Kw 

 

 A stove with a higher output can be used if it's run with a lower fuel level. With some experimenting, you will quickly find the fuel loading that is right for your comfort. A small increase in the heat output may be required depending on the number of windows, doors and level of insulation in the room.  A new build is roughly built after year 2000 - this will have a higher insulation efficiency.

All modern appliances are rated in kilowatts. For conversion to British Thermal Units (BTU), multiply the kilowatt rating by 3400.

Clearances for solid fuel stoves

When installing a stove into an inglenook setting it is important to allow adequate clearance around the stove. This allows air to circulate efficiently in the room, grants access to any controls on the side of the stove and also protects both the stove and surroundings from any damage by excess heat. Manufacturers differ in their stated clearances, so please refer to each individual recommendations.

Hearths

The idea of a hearth for a stove is that the stove sits on a slab of non-combustible material that protects any combustible materials underneath and around the stove from the heat of the stove, and from any burning fuel that might accidentally fall out from the stove.

If burning fuel falls from the stove then the hearth should be of sufficient size that it lands on the hearth and not on the floor, carpet, or other combustible material. The edge of the hearth should be at a different level from the floor to clearly define the safe perimeter - you can easily do this by making the hearth higher than the rest of the floor.

We can supply a range of floor plates (a floor plate is also a hearth) made from different types of material - please ask.

Hearth size and thickness

The stove must sit on a hearth of non-combustible material extending a minimum of 150mm (6") from the stove at the sides and 300mm (12") in front.

Some stoves can sit on a 12mm hearth such as glass, steel or slate but it is advisable to check each manufacturers recommendations.

A one piece hearth or back panel is not usually suitable for a solid fuel stove, they do not allow for expansion and contraction and may crack.  Our HETAS installer will be able to advise you, hearths of one piece construction are often designed only to be used with a gas or electric fire, they may even be constructed of combusible material.

Hearths for freestanding stoves

The minimum hearth size for a freestanding stove is 840mm x 840mm, as the stove may heat the hearth to over 100 degrees.

Once we have discussed your requirements and ensured that your chosen stove is suitable we will arrange a convenient day for a qualified HETAS installer to visit your property to survey the site, advise on hearth size, any structural alterations required and to prepare a quote for installation.

Chimney Liner

It is always good practice to line a chimney when fitting any stove, whether it is a woodburner or multifuel stove.

If stoves are burning for long periods at a low temperature (slumbering), it is highly recommended to use 904 grade liner, which is more resistant to corrosion.

We also recommend flue lining for the following reasons:

  • Better future safety for old chimneys.

  • Improved stove performance

  • Easier to clean - meaning less chance of chimney fires.

  • Reduces the size of the chimney, therfore suiting your intended appliance.

  • Stabilise the flue draught, which reduces potential chimney problems.

There are two grades of chimney liner:

316 grade should be used for more occasional use and when primarily using wood.

904 grade liner can also be used when burning wood, but it is designed for the higher temperatures of smokeless fuels.

Please ask about chimney liner prices.

Multifuel vs Woodburning stoves

Multifuel stoves have a grate upon which the fuel burns and an air inlet which allows air to enter from below. A pan catches the ash as the fuel burns, so that it can be taken away. Multifuel stoves offer the flexibility of burning a combination of wood and coal.

Dedicated woodburners have no grate or ashpan, the fire sits on a bed of ash in the bottom of the stove, wood fires perform better with air entering from the side or above the seat of the fire.

Many stoves can be converted to be either multifuel or wood, it is a simple matter of removing the grate and fitting longer fire bricks in the combustion compartment.

Carefully read all information regarding the method of running your stove, practices such as 'slow burning' certain types of smokeless fuels may lead to a sharp drop in the life of your flue liner - which will not be covered by your guarantee.

A Cleanburning wood stove, sometimes referred to as Cleanheat Stove

These stoves will burn wood very efficiently. When you 'burn wood' in a stove, it's actually the emitted gases which burn, not the wood itself. This gas needs oxygen from air, which can be quickly used up. By introducing a fresh supply of oxygen above the fire, gases that otherwise would have been sucked up the chimney are burnt. This is referred to as Secondary Combustion. It creates extra heat, so clean burning stoves will often have a higher heat output than the non clean burn model (as well as reduced emissions).

Combustion and efficiency are increased by heating the air supply - this is done by drawing the air through channels next to the hot firebox of the stove before it is directed to the top of the fire. Wood burning stoves which have air inlets at the top of the stove and stoves with airwash will tend to be more efficient as the air is getting to the fire from above, but they will still not be as efficient as a cleanburning stove.

Some Cleanburning woodburners have approval for burning wood in smokeless zones because their emissions are lower. Please speak to a member of staff to ensure that you have the latest designs and information.

Cleanburning stoves generate more heat through the burning of these otherwise wasted gases, you will find that Cleanburning stoves have a higher output than a standard stove, they are more efficient and therefore use less fuel.

As a service to our customers we provide a list of types of wood and their qualities as firewood. We provide a list of wood suppliers in your area, generated by recommendations from our customers.  We welcome your feedback.

What should I do next?

Once you have all your measurements and preferences worked out - choose your stove! Remember, we are here to help.

If you are unable to have a woodburner or multifuel stove in your property you may wish to look at our range of electric or gas powered stoves.

Electric: The amazing new Optiflame has an electric flame, smoke and flame effect with stunning 3D realism. Just plug in and go! No flue, no mess, no hassle - installed in minutes. Flame and smoke only setting and 100% energy efficient.

Gas: We have several models in the gas stove range. The choices include different conventional flue gas stoves and different balanced flue stoves, even a portable gas bottle option. There is a gas stove for almost any situation.

Would you like an indication of costs etc for your fire, fireplace, wood burner or cooker? Just email us at kaye@derwas.co.uk or use our contact page

Please give us as much information as possible, here is a suggestion list of useful information which will help us inform you:

Pictures inside & outside the house would be brilliant. Anything which may affect the stove/fireplace/chimney

Do you just wish a 'ballpark figure' or have you a plan to have everything fitted before a set date?

Please let us have a brief description of what you want done & what you expect from the outcome

Have you seen any stoves/fires/fireplaces that you like?

What is your room size, w x d x h?

What fire is in situ?

Is there an air vent?

Do we have to 'knock out?' (i.e. make a hole/remove existing)

Do you have a chimney?

When did you last have it swept?

What is the depth of the chimney breast?

Does it project into the room or is the wall flat? If possible, please supply pictures from about 6 – 8 ft away to give perspective

What size is the hearth? (You will need up to 12" in front of a stove)

What is the hearth made of? (Hearths designed for gas or electric fires may not be suitable for solid fuel appliances)

What height is your house? (bungalow, two storey etc)

What is the age of your house?

Any pictures showing any of the above available?

Any pictures/information ref the outside of the house with regard to access?

Click For Directions

Dragon Works
Henfaes Lane Industrial Estate
Welshpool Powys SY21 7BE