What is a Chimney?

Although they are no longer as necessary for heating most homes in the UK thanks to central heating systems, your chimney likely once played an integral part in keeping your home warm. The fireplace chimney is designed to protect people inside the home by providing a vent for smoke, sparks, and toxic fumes that are the result of lighting a fire in the fireplace.

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Since warm air rises, it creates an updraft that pulls the surrounding smoky air along with it. This updraft of air up through the chimney is very strong, helping to keep rooms free from smoke and soot when a fire is lit inside. Chimneys have various parts that work together to create this mechanism.


Chimneys are often fitted with dampers, which are plates that can be used to cover the chimney opening. A damper can be installed in chimney caps or at the base of the chimney and is opened or closed using a lever located just inside the firebox.


The flue is the passage through the chimney to the outdoors. One chimney can contain more than one flue if there are more than one fixtures or appliances using the chimney to vent smoke. There is an access door located at the base of the chimney flue where debris accumulates.


A chimney liner is a protective layer fitted to the inside of the chimney. It is a must-have in any modern chimney and is designed to dissipate the amount of heat that comes into contact with the building materials surrounding the chimney, reducing the risk of fire. Liners are made from a variety of materials including aluminium, stainless steel, terracotta, and other fireproof materials.

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The chimney stack is the very top part of the chimney and the part of your chimney that you can see from the outside of your home. While most chimneys are not in use now, you can usually tell when a home has a traditional fireplace in use since there will be visible smoke coming out of the chimney stack.

If you use your chimney for fires, it’s important to keep it clean and well-maintained. Chimney fires burn hotter than you think, which is why it’s so important to ensure that the chimney components, particularly the liner, are in good repair. Having your chimney inspected and cleaned by a professional on an annual basis is essential if you are using it to heat your home.