gas flue?

no, certainly not without your permission. the flue should be at least 300mm from the boundary. if the discharge from the flue is causing a nuisance then you may be able to agree with your neighbour to have a plume displacement kit fitted (if it's a condensing appliance) rather than moving the flue, but it's really up to you to agree on a solution with your neighbour. another common solution is to have a vertical flue fitted, depending on the layout of the building.

Ian
August 2010

nothing should be over your boundary line at all.
def not a boiler flue

hi-spec plumbing & heating (essex)
August 2010

600 mm in most cases

b
August 2010