You don't need to be an 'investor' to invest in Singletrack: 6 days left: 95% of target - Find out more
Have a log burning stove and the chimney has a metal flue lining to the chimney.
Do these need to be swept or does the metal keep it clean?
No - you MUST clean it. Soot builds up quite quickly. If your logs aren't seasoned well, you will also be throwing up lots of sticky gunk which th soot likes to grip to.
I would say every other year is sufficient if it occasional use, but if used all the time I would recommend sweeping every autumn before it is fired up for thefirst time.
Also - have it regularly checked for leaks as stoves (due to the immense heat output) can soon put paid to a metal flue.
Should be swept annually, but depends on how much you use it, how much draft their is and what sort of wood you burn.
For the sake of £30 its not worth not having it done.
Bloke I had come round and quote me for a log burner said annually is the way to do it.
You don't want to risk a fire up the flue.
You probably need it swept more regularly with a liner (metal flue) than a conventional (old - traditional) brick flue, because the diameter is so much smaller. The efficiency is greater with a liner but it is calculated on that small diameter flue - so sweep it regularly (twice a year if it supplies a water heating system).
Personally, I don't like liners in old buildings, it causes condensation in the brick flue that it's inserted into to. Great for new builds.
My brother had a chimney fire in his house last week. put some candle ends on it which were left over from Christmas (tit) entire flue caught light - its a huge Yorkstone lined barn conversion, massive chimney, could practically walk up it. Basically the wax allowed the soot to catch light.
Cowling on the top of the chimney to stop rain/birds melted, stone cracked half way down the chimney. Fire brigade called...
Big...big clear up job...smoke damage to half the barn..
For god sake get it swept!