Somewhat wryly I suspect this is a NICEIC?
The law is very clear, specifically...
1. BS7671 is not retrospective (MEB presence/sizing is a requirement for supply)
2. BR are not retrospective
3. IEE regs permit Jn Boxes as long as they remain accessible
4. IEE regs permit Crimps which are not accessible
Note the condition for "3" - ACCESSIBLE.
If the location is under floorboards...
- They should not be in a place where furniture is likely to be placed
---- eg, under the landing is ok, anywhere else most likely not
- They should have a hatch fitted if laminate flooring fitted
---- eg, laminate flooring over landing floorboards
- They should be documented for fault finding
You can NOT stick laminate flooring over floorboards with JnBoxes below.
- It turns "accessible" into "inaccessible"
- Get a Bosch PMF180E or Fein Multimaster & "plunge cut" access panels
- Such tools create a 1mm wide cut without effort, then appropriate fastener
- Realise they are deafening on any surface than can reverberate
If the JnBox is damaged.
- You do not have to change all cables or rewire.
If the wiring fails IR EFLI Visual.
- You will need to replace the cable(s) and THEN may choose to wire via Ceiling Rose "JnBox".
- Ceiling Rose "JnBox" is inappropriate if you need to add lighting later because a ceiling rose is not likely to be accessible for additions of cables
If there are JnBoxes present.
- You do not have to rewire IF they are accessible, IR ok, EFLI ok etc
- Tell him to cite 1) BS7671 reg stating JnBoxes are not permitted 2) where BS7671 or BR are retrospective.
- If he says it is "the law", simply throw him out
If in doubt, find someone else.
- Faults are those based on comparison with BS7671 regulations
- Otherwise any could invent whatever to meet remuneration needs
Ceiling Rose Jnbox is preferred by many.
- All cables are accessible from within the room
- Fault finding very much easier & faster - time is money
- Inaccessible to add cables to later
Accessible JnBox loop-in is preferred by some.
- Accessible to add cables to later unlike central ceiling roses
- Fault finding can be simpler
- Permit more complex lighting systems (DIN rain in adaptable box)
Argument specifically by some NICEIC is often that only a ceiling rose is accessible. That is until a client wants to add cables to said ceiling rose, stuck in the centre of a room, under laminate floor, carpet & bed.
Ceiling Rose JnBox are LESS accessible for cabling additions.
Ceiling Rose JnBox are MORE accessible for inspection.
That said I hate JnBoxes in lofts re access & boarded-over.
However in itself no law means that in itself necessitates a rewire.