Is my neighbour's flue too close?

[Goonermatt]

I live end of terrace, and my neighbour has moved their boiler so that their flue is now around 100-200mm from the boundary between our gardens.

Everyone else's flue comes out right in the middle of the back wall of the house, but next door moved their boiler (and also have one of those retractable awnings) so that the flue is now almost where our houses meet.

I have contacted everyone who I thought might be able to tell me if their flue is too close but keep getting conflicting answers.

I've been told that it should be 300mm from any opening door or window, which it is, and that it should be 600mm from a boundary. But does that only apply when the flue is pointing at the boundary? The only diagrams I can find (including BRs Part J) make it look like the flue needs to be 600mm from the boundary if it's pluming towards it.

As it is, the neighbours flue points into their garden, but is only around 1-200mm from the 'boundary' where our houses are split.

I only want to question it because we had an activated CO alarm and while the national grid and BG said there was no issue at our place, BG man said that next door's flue was 'too close' (but failed to tell me how far it should be) and could have been the cause of the CO alarm activating.

So essentially, is it too close and who do I get on the case, if the neighbour won't do anything, because my borough's building control said I should take it up with Gas Safe Register, who said it was a Building Control issue!

Thanks.

[The Builder]

Matt, maybe part of the confusion comes from the fact that the distance depends on the type of flue being used.

"...from an internal or external corner OR a boundary alongside the terminal"

i.e. pointing into their garden. The dimension can be 200mm, 300mm, 600mm, depending on whether it's balanced flue or open flue, and on whether fanned draught or natural draught.

So, 200mm may be right.

Also, in my humble opinion........... assuming it was fitted by a Gas Safe guy, then Gas Safe have a duty to monitor their members.....
and........... it is, by definition, a Building Control Regulation.

So............. both bodies should show an interest in this case, rather than the usual bureaucratic buck-passing.