Distance from a metal chimney?

[Octopus]

Got a small job to do this week, re-routing some cables away from where a new metal chimney is going for a wood burner and I was wondering if anyone can point me at specific regs or building rules about the proximity of cables to such devices??

Thanks

 

[Marvo]

Is the chimney double skinned with insulation? You may have specific regs but I'd suggest about 200mm (about 8"). Wood burner chimneys are particularly prone to internal fires due to carbon build-up and I've seen a couple of them that have been hot enough to make the galvanising run down them so if it's single skinned maybe play it safe with a larger distance.

 

[Guest55]

I was wondering if anyone can point me at specific regs or building rules about the proximity of cables to such devices??

Thanks

theres nothing specific.
however as your t&e cables are rated for 70 degrees C then you need to make sure they are routed in a place alot cooler than that temp.

 

[Richard Burns]

I just did a quick estimate of a 5kw stove with 10% heat output to chimney and with 200 C at chimney with brick at 1W/mK then 35cm of brick would keep the cable at about 30 C so I would agree with Marvo.

 

[Guest55]

i'd just use common sense rather than looking for a technical solution.

 

[JD6400]

A chimney fire will burn at well over 1000 degrees f , i think most guides state 150mm from any surface if twin wall and 300mm if single skin ( And that is a inflammable surface as well i think ) .
I am not hetas so don't be taking my word for it though !

 

[Octopus]

I was thinking of using 300mm or 12 inches in old money so looks like I'm on the right track.

Thanks