Chimney lining specialist in the Royal Tunbridge Wells area
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01892 319315
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Air starvation – When a flue is unable to draw enough oxygen or air from the nearby room to feed the flames and operate the appliance properly.

Approved Document J – An official information document giving the procedure needing to be legally followed when installing a combustion appliance that meets building regulations.

Balanced flue – An appliance which is vertical or horizontal located on the outside where the flue outlet and air inlet are found.

Bedding – Fixing a chimney pot, liner or similar within a mortar bed or joint compound.

Bend – Changing direction within the flue, often returning to a vertical position.

Boiler – The appliance with a heat exchanger which allows water to be heated and the energy transported around a property.

Canopy/Hood – A visible and often decorative metal gather placed over a basket grate to retain gases and pull them back inside the flue.

Capital Cost – Installation costs for the initial set-up including the appliance, fuel storage and any fuel.

Carbon Monoxide (CO) – A gas which can prove lethal to human beings. It is formed by carbon burning in a space without oxygen.

Cast In Situ – Casting the liner into the flue rather than in a different model and adding the flue at a later date.

Central Heating – Heating an entire home using a central boiler or warm air heater.

Chimney – A property structure with one or more flues used for fires.

Chimney Stack – Part of a chimney which shows above a roof.

Chimney Terminal – A capping or top on a chimney.

Combustion Boiler – Two heat exchangers combined in one unit system to warm up water drawn from taps and heat water around radiators.

Combustible Material – Flammable material.

Condensates – When a temperature is cold enough to change vapour into liquid in a flue.

Condensing Boiler – A clever method of getting extra heat. This is a boiler which gives out lots of heat from combustion products causing them to condense at the heat exchanger which causes a greater volume of heat efficiency.

Constructional Hearth – Most solid fuel appliances use this type of hearth, usually located on a floor and the base of the fireplace recess. This position helps keep high heat levels away from the structure below these appliances.

Corbelling – Brickwork which is stepped and formed into an offset or gather which can be placed at the highest point of a chimney stack to create a drip course or oversail.

Decorative Fuel Effect – When the effect of a wood-burning appliance or real solid fuel is imitated by an appliance.

Decorative Hearth – A decorative touch which is also safety-orientated to make a constructional hearth more secure for a homeowner. The decoration, a difference in paint marking, for example, creates a level change from the floor to indicate where to keep any rugs, carpets or other flammable material away from the appliance.

Dog Basket/Dog Grate – The basket used to burn fuel or the gas burner utilised to give the impression of a fire.

European Normative Standards – Standards universally adopted by the European community known as BS EN in the UK.

Factory-Made Chimney Systems – Prefabricated chimney systems but especially denoting to those made from steel.

Fireplace – The structure with a decorative frontage which is placed around a fireplace or appliance.

Fireplace Opening – The opening of the site for the fire within an open fire set-up and surrounding structure.

Fireplace Recess – An appliance or fire will sit in this structure which can be furnished with a decorative fringe and a British Standard fireback to help position the centre of the flames.

Flashing – Material such as lead used to waterproof joints between chimneys and roofs.

Flaunching – Cement used to hold chimney pots in place. It can also be used for fireplaces, sculped over the fireback to make the path for the flue gases smoother.

Flexible Stainless Steel Liners – Liners made of stainless steel which are either one skin or double skinned and sold in lengths. They allow lining to flow from the top to the bottom of a flue without any joints.

Flue – A gap inside a chimney created so that fire gases can escape to the outside atmosphere.

Flue Liner – Material used within a flue inside a chimney stack .

Flue Pipe – A pipe connecting a flue with an appliance outlet.

Flue Spigot – A socket allowing a flue pipe to fit into an appliance.

Flue Terminal – The terminal utilised for a flue such as a chimney pot.

Free-Standing – When an appliance is sited apart from the chimney breast but connected via a pipe.

Gather – A gap above the opening of a fireplace where gases collect in the bottom of the flue and are helped to move quickly upwards to the outside, particularly if it is smooth.

Heat Exchanger – The structure which collects heat from the fire and passes it to water or air to heat a room or other parts of a property.

HETAS – This stands for the ‘Heating Equipment Testing and Approved Scheme’ – an official body which tests and approves products and services related to solid fuel, including approved tradesmen and appliances.

Inglenook Fireplace – A room extension which contains a small fireplace or stove in the rear.

Inset – An appliance which is constructed within the breast of the chimney.

Midfeathers – Any walls separating flues within a multi-flue chimney.

Natural Draught Flue – A type of flue which allows the draw of air naturally rather than as a result of a mechanism or a pressure system.

Offset – A flue section which is not vertical with two bends and a straight section.

Offtake Pipe – Piping which directs gases from a flue in a direction from the appliance to the flue via an inset set-up.

OFTEC – This stands for ‘Oil Firing Technical Association’ which accredits professionals with the task of setting up oil-fired appliances and related pipes, as well as transporting oil to the property to be used as the fuel source.

Oversail/Drip Course – A clever method of at least one course of bricks built to jut out from the main chimney stack. This allows water from condensation and rain to drip onto the roof.

Part Per Million – The amount of gas molecules per million molecules of air and/or combustion products.

Period Fireplace – A common phrase for a bigger fireplace.

Perlite – Fireproof material which is natural and is light in weight but also excellent for insulation.

Pointing – Exposed mortar in joints located within wall bricks or the chimney stack. It is modeled to let rainfall flow away without affecting the joint.

Prefabricated Chimney System – When a chimney is made from various factory components such as concrete blocks or steel tubes.

Products of Combustion – Various gases caused by smoke and fumes which emit from a fire.

Proposed European Standards – Standards in building practice yet to be agreed by the wider European Community, known as prEN with a follow-on number in the UK.

Pumice – Volcanic rock. It is useful in some block chimney systems and concrete chimney liners.

Ranger Cooker – A useful open fire which contains a number of flues and ovens which allows for cooking.

Rear Outlet – A particular appliance which is made to allow flu gas to depart at the rear.

Roof Lantern – A roof hole cover needed for central hearths.

Room Heater or Stove – An appliance for solid fuel or wood burning but often useable for other fuels, made with a front door glass panel.

Sectional Liner – A special acid-resistant flue liner made in sections and used in the flue, often when construction takes place.

Smokeless Fuel – Fuel which is solid and makes less soot and other combustion products when burnt. Yet it does contain smoke and gases which are not so visible but they can still be harmful.

Solid Mineral Fuels – Solid fuels taken from the ground when extracted, such as smokeless fuel or coal.

Superimposed or Decorative Hearth – A floor section which has been raised to prevent furnishings being near an appliance.

Throat – A constricted gap above a fireplace, and in the flue, which slows down the intake of air from the room whilst pushing air movement to get smoke up the flue.

Top Outlet – A type of appliance allowing flue gases to depart from the top of the stove rather than be vented from the rear.

Vermiculite – Fireproof material that is natural and given treatment to become both insulating and light.

Void – A big gap inside a flue or the area above any given fireplace.


TLC Stoves and Liners – Explaining terms used in the industry.