clarification on downlighters needed

[jackfrosty]

Hi, just need some clarification really. If changing an existing bathroom light for 3 IP65 fire rated downlighters on a 16th edition consumer unit with only RCD protection on the sockets will i have to use a RCD spur or will i be ok just just wire in new lights without RCD because i will not to putting any wires in walls etc.

Also the above the bathroom is a insulated loft, is it ok to just remove insulation around downlight as i am using fire rated downlight so dont have to worry about fire hoods etc? I have been researching online fire hoods etc online for hours and i keep getting contradicting answers and has sent my head spinning

thanks

 

[m4tty]

I think as your working on bathroom lighting circuit it will need rcd protection but wait for more experienced peoples comments. I see where your coming from tho but I personally would want them on rcd. You got to sign the cert so it's your name. Are they 240v or elv?

 

[m4tty]

Can't you move the mcb to the rcd protected side. Or have a swap around so your circuit is rcd protected?

 

[sparkytim]

Are you adding any wiring?

Then that will be an addition and needs to comply with current regs.

 

[m4tty]

Are you adding any wiring?Then that will be an addition and needs to comply with current regs.

Think he's saying any additional cabling will be in ceiling. Not in walls. So will they still need rcd protection. I still think so

 

[jackfrosty]

Yeah adding more lights so will be extra wiring. Il have a go with putting the lighting of the RCD side of the board though thanks for that idea matty.

Is it acceptable to have a RCD spur in the loft? cant see how it will get tripped much it ever and could put on minor works certificate it is up there

 

[NozSpark]

The main reg that applies here is RCD protection of bathroom circuits!

So as it's not a like for like replacement and you are in fact adding to the circuit within the bathroom it will require RCD protection, now ow you do this is up to you IMO; you could replace the MCB with a RCBO, add a RCD in an adjacent enclosure or add a RCD FS just for the bathroom portion of the circuit (ducks for cover)

Regards to fire hoods and insulation..

fire hoods are only required if you breach a fire barrier and there is a habitable room above

insulation should be removed from around the fitting, however it should not be removed. You could fit a loft box and then re-instate the insulation over the top or a cheaper option is to use plasterboard instead and batten on top of the joists to give the required extra height... most downlight manufacturers state that you should leave 150mm free space around the back of the fitting.

 

[Zeespark]

Why not just intall an RCBO at the board and save install time over an RCD spur?

AndyGuinness

 

[m4tty]

If you do that I'd put a label on the board saying bathroom lighting rcd is in loft as they may loose the cert and if it trips they will definitely go to the board.

 

[NozSpark]

RCD FS in the loft is not a very good idea...

think about accessability of accessories!

I'd normally fit them above the door

 

[PC Electrics]

What's wrong with using an RCBO?

If you must use an RCD FCU, put it next to the board (covering the whole lights circuit) or over the bathroom door or in the airing cupboard - anywhere accessible.

Make up plasterboard boxes for behind the lights. Make them about 0.8 to 1 cu ft to allow heat disipation. Then you can reinstate continuous insulation (as required by building regs!).

 

[kme]

+1 to PC

 

[jackfrosty]

is a RCD single fused spur ok to run a whole lighting circuit as opposed to an RCD in a single enclosure?

 

[tom1]

is a RCD single fused spur ok to run a whole lighting circuit as opposed to an RCD in a single enclosure?

rcd fcu are rated up to 13 amp i belive, so just put a fuse in to suit.

The mcb will be there also

 

[spinlondon]

The requirement as has already been posted, is to protect the circuit.

There is some disagreement between members of the forum on whether this requirement to protect the circuit refers to all of the circuit, or part of the circuit.

My understanding is that it refers to all of the circuit. If only part of the circuit is protected, then any earth faults upstream from the RCD will be able to by pass the RCD thus allowing earth voltage into the special location.

As such the RCD should be either at the CU, or as close to as practicable.