Does my Flue need lining?

Your flue will need lining if it leaks or if it is not of a suitable size for the appliance connected to it. If you are considering a wood burning stove or similar, these are designed to work best on a particular size of flue. The standard size of flue for a stove is 150mm internal diameter and with a flue of this size the draught entering the stove is more controllable.

Stoves work best with a flue diameter that is close to the outlet size. Flues should never be smaller than the stove outlet diameter.

Defra Stoves.

If a Defra Stove is fitted however, this diameter can be reduced to 125mm. This matches the stove outlet diameter. Defra stoves are great. They are more environmentally friendly and use less fuel. Glowing Stoves will always recommend these stoves. Google Defra for more info. Call us for our recommendations.

What happens if the flue size is too Large?

When the flue is too large the internal flue temperature can often be too cool. This can cause moisture in the smoke and fumes to condense creating tar and soot build up. It can also create damp areas in your flue. Do not do it. Your flue interior may rust internally over time.


So when asking the question ‘does my flue need lining’, our thoughts are yes. Get a decent quality liner that is a close size to the stove outlet. Never get a liner that is smaller than the stove outlet. Its against Hetas regulations. We like to use Duraflue liners. They are strong and well made. Sure they are more expensive, but they last a long time.

You get what you pay for with liners. Call Glowing Stoves for advice. We will be happy to help you however, whether or not you use us.