If you choose to have a chimney liner, there are regulations you need to follow to make sure that you are installing it safely. One of them is using the right size flue for your stove.
Any new stove you buy, the manufacturer should state what size flue liner you should install with it. A rule is never to use a smaller flue liner size than specified and make sure you use the right liner for the right flue. Both of these are serious safety hazards.
The general rule is as follows:
- For a stove of up to 20kW in power, a minimum of 6” diameter flue is needed.
- A 5” flue liner can be used if you have a DEFRA approved stove & the manufacturer clearly states this is compatible.
The size of the stove collar does not necessarily have to correspond to the size of flue liner you need. If your stove collar (where you attach the stove pipe) is 5” but you need a 6” flue liner, then adapters are available for you to do so.
When it comes to the length of your flue, you need to ensure that your flue liner is long enough to reach the top of your chimney from the bottom.
Sticking two pieces of flue together though is against regulations, dangerous and unsafe. If you need to order a flue liner it is better to over-order the length you need and cut down what you don’t need.
A professional chimney installer will be able to measure your chimney length for you.
