I think you have misunderstood my post SpecialI have not implied that cable buried in insulation requires protection.
As I stated in my post.
"There is no requirement because of the type of insulation that would require a cable to be run in conduit."
As for the rcd protection, you have to take responsibility for the whole circuit if you are to extend or alter its length, and give a mwc for such work.
without prior knowledge of the exact cable run, you would be responsible to protect that circuit under the new provisions of the wiring regulations and provide "additional protection".
Agreed insulation has negligible affect on cable capacity in this instance ..
but unfortunately GH you are incorrect with your assessment of what you actually sign for..
You take responsibility only for the work that you do.
NOT the whole circuit, or installation for that matter.
The declaration you sign says that "the said works do don't impair the safety of the existing installation"
Check with the sample MWC declaration page 150 on-site-guide, part 4 declaration.
And as the regulations are not retrospective there is NO requirement to do upgrade to the existing circuit...
unless of course, your addition would bring some serious safety issue to the rest of the circuit.
In this particular instance of Bobs work, you would be signing to say that your extra few meters of cable are electrically safe & the total circuit length is still with limits meting Zs, and ins res is OK etc..
but if no RCD already present there is no need to fit one.
However had this been adding a socket not a light fitting there would be requirements to ensure the socket outlet is RCD protected. to ensure compliance with 411.3.3.
The landing is not a special location however you are not allowed to place an electrical fitting in such an enviroment as to cause a hazard to the user.
If the user has to over reach to change a lamp or for cleaning etc you have created a hazard. Just common sense and to prevent electrical points from being placed in situations that an increased risk is imposed on the user.
You are of course correct on all points and I would always recommend work to be carried out by a qualified person for the reasons I stated in my post.
As qualified and competent persons we do have to be careful about how we describe what is permitted / not permitted / just good guidance / or statutory obligation under part p.
You "are allowed" to stick your landing light where you like.. there may be more practical or preferable positions..
but you most certainly are allowed as we all know BS7671 is a NON statutory
document, just guidance or good practice.
please don't take this as a dig at yourself GH:x
but we just need to be sure we don't modify the regs to our own versions..
especially on an open forum.
