How often should
my chimney be swept?

Based in:


East Sussex.

01424 224222


The answer to this question, is dependent on a number of factors.

What type of appliance is it?

What fuel are you using?

Do you have a cowl on the chimney pot?

OK, so, let’s start with a gas fire. In general a gas fire will not produce soot, so sweeping is not necessary 

UNLESS birds or squirrels have tried to make their homes in your nice warm chimney! This is very often the case, and can cause a danger to your health. by stopping the flue gasses escaping up the chimney thereby allowing them to build up in your room, as CARBON MONOXIDE. Jackdaws are the main culprits, here. They start by dropping large twigs down the chimney until they start to catch across the opening and then build up from their until it can support their weight. they then put moss and other softer material on top of that. By this point the chimney is totally blocked. when they vacate the nest, the starlings move in! I have removed nests that are over six feet thick! Unfortunately timing is the key here, as Jackdaws are protected. so if you discover a nest that has unfledged babies in it, you cannot disturb it until the chicks have flown. Meanwhile, obviously, you can’t use your fire. Luckily this only happens in the summer months, when you probably wouldn’t need the fire anyway.

The answer here, is to have your chimney checked and a suitable cowl fitted. Always seek expert advice when choosing a cowl and not just the ‘best guess’ of a salesman from your local builders merchant. i have seen so many people waste their money in this way.

A lot of Class 2 gas appliances have fully lined flues, with a GCI terminal on the top. these should never need to be swept, although the draw should be checked during every annual service.

Solid fuel appliances....The chimney should be swept AT LEAST once a year and very often twice a year if used regularly. This applies to open fires and stoves, whether the chimney is lined or not. If you are burning wood that is not well seasoned, or soft woods like pine etc. you may even need to have it swept more often! Believe me, a sweep is a lot cheaper than repairs due to a chimney fire or worse, death from carbon monoxide poisoning. Remember when your solid fuel fire is starting up or burning down, it produces 1000 times more carbon monoxide than a faulty gas appliance, so if your chimney is getting blocked due to soot or tar build up, that CO will escape into the room and there are no safety features on an open fire to prevent that! ALWAYS make sure a co detector is fitted in the room IN THE RIGHT PLACE and that it is working correctly.

Once again, birds can be an issue as above, so a suitable cowl with bird guard is pretty essential.

Electric fires will always be fitted with the chimney blocked off with fiberglass, so not an issue.

Back to General InformationGeneral_Information.html