18 Mar 2022

Fireplaces provide warmth and add character to your home, so they’re often considered to be one of the favourite features of people’s properties. But have you ever wondered whether all your fireplaces are connected to the same chimney? 

When it comes to the chimney structure, it’s a bit more complicated than you may think.  

What’s the difference between a flue and a chimney?

To find out whether all your fireplaces are connected to one chimney, you first need to understand the difference between the chimney itself and a flue. 

Most people are unaware that the chimney is actually the whole structure, whereas the flue refers to the inside of the chimney where smoke and gases travel. So, a flue is the inside of the chimney, which can be made up of original Georgian brickwork or steel flexible liner.  

Whether you’re a new homeowner or fitting a new fireplace, it’s very important to ensure that the flue is swept, inspected, and tested before use, to make sure it’s safe to use.  


How many fireplaces do homes typically have? 

How many fireplaces your home has will largely depend on the type of home you live in. Before the 1940s, for example, it was very common for homes to have a fireplace in every room of the house. So, although the original fireplaces may have been removed, it’s likely the flue has been closed off. 

Each fireplace will have its own flue within the chimney structure. Although the fireplace may seem to be directly in line with the flue, the lower floor flues will bend to avoid the fireplaces on the floor above and will run side by side.  



What does the structure of the flue look like? 

If you have a chimney, you’ll probably have noticed that your home has a lot of chimney pots on the top. Each pot is the top of a flue, which runs to a different fireplace within the house.  

Within the chimney, flues are often separated by a single brick. These bricks are referred to as mid-feathers. It’s very important that each flue remains separate and structurally sound. 

It’s not possible to get inside a flue and carry out repairs, as this brickwork can often be in a very bad state and certainly not sufficiently airtight to safely evacuate fumes from your house. 



What can I do to ensure my chimney is safe? 

Inspections are vital. If the flue is leaking, the leak usually originates between the flues. This is impossible to detect without a proper inspection. The flue must be CCTV inspected to check the condition, so that an appropriate lining method can be recommended.  

While it isn’t possible to inspect the flue yourself, there are some signs of a leak that you should look out for. For example, if you can smell something emanating from the chimney from the fireplace in another room, then this could be a sign of a leak, and the flue must be inspected and tested before use. 

Bear in mind that in a lot of cases flues from a neighbour’s property can overlap in the loft space. If you can smell your neighbour’s fire, then the flue must be checked by a professional. At SweepSmart we’re experienced and qualified in this area, and would be happy to help. Do get in touch if you have any questions relating to chimneys.