Chimney Sweep - FAQs

Why do I need to have my chimney / flue swept?

Chimneys need to allow the free passage of dangerous combustion gasses. Regular sweeping will remove soot, bird nests, cobwebs and any other blockages. It also removes creosote, which will help to prevent dangerous chimney fires. Chimney Sweeping will also increase the efficiency of some appliances.

How often does my chimney need sweeping?

Frequency will depend on a number of factors which include the type of fuel used, appliance, duration of use, moisture content of wood fuel, and the type of chimney you have. Your NACS Chimney Sweep will be able to advise on the sweeping frequency during the appointment. The sweeping frequencies below are for guidance purposes only:-

• Smokeless fuel: At least once a year
• Wood: Quarterly when in use
• Bituminous coal: Quarterly when in use
• Oil: Once a year
• Gas: Once a year

Why should I use a NACS Chimney Sweep?

NACS Chimney Sweeps undertake a rigorous training course and have to successfully complete a full assessment prior to becoming a NACS Member. All NACS Members must hold valid insurance for Chimney Sweeping, of which they provide a copy of to the Association on an annual basis. They must also have the correct equipment to be able to undertake the job which is checked at the time of their assessment.

Will having my Chimney Swept make a mess?

NACS Chimney Sweeps are very mindful and conscious of making as little mess as possible, and are in fact trained in the prevention of dust escaping during sweeping. However, there are exceptional circumstances e.g. if a chimney may be blocked with a birds nest, which makes it difficult to guaranteed that no mess will be made.

What should I do to prepare for the sweep’s visit?

Normally they will need a clear passage to the chimney and adequate space to work in. They may suggest you clear any ornaments from the hearth and mantelpiece, and perhaps you could clear the grate of any fuel, ash or rubbish etc before the sweep arrives.

Do I need to have my gas/oil flues swept?

Yes, although burning these fuels does not normally deposit soot, there are still numerous other problems which can affect chimney function which sweeping can solve or identify. It will also help with the prevention of chimney fires and even carbon monoxide poisoning.

Why do I need to see the brush out the top of the chimney?

NACS Chimney Sweeps normally show you this to demonstrate that the flue has been swept throughout its length.

How much does it cost to have my chimney swept?

This depends on a number of factors including the type of appliance or chimney you have, the time the job will take to complete properly, and the location within the UK.

I’ve just moved house – do I need to have my chimney cleaned?

Yes, as you may not necessarily know when it was last cleaned properly by a professional Chimney Sweep.

What is the best fuel to use?

For certain appliances there is a recommended fuel which is the one that should be used. In appliances where there are no such requirements, there are several things that need to be taken into consideration when selecting fuel. Wood that has been properly seasoned is commonly used as it is clean, gives good heat and is carbon neutral.

However, some people prefer using coal as it suits them better. If you are thinking of using coal, then we recommend you use a local approved coal merchant who will have the expert knowledge to guide you.

Please remember that some areas of the UK are smoke free zones, which must also be taken into consideration when selecting fuel.

Why do I need my chimney swept before it is closed off?

If a chimney is closed off, it can become damp. If there is soot in your chimney, then this soot can turn into a black acidic slurry that in an old chimney can soak into the internal walls causing severe problems. If the damp gets bad, then it can penetrate through the wall into the room where it will cause unpleasant stains on the walls.

Why are there smoke marks just above the fireplace?

This may be caused by smoke leaking back into the room; call your local NACS Chimney Sweep to seek their advice as soon as possible.

A bird has come down my chimney, how do I prevent this happening again?

Seek the advice of your local NACS Chimney Sweep who will be able to advise you on a suitable terminal / guard for your chimney.