Maintenance free junction box under floorboard

[TryAgain1]

I'm 'making good' an existing electrical installation in a terrace alongside lowering the ground floor ceiling. As such with the electrics under the upstairs floorboards I am doing:

-Clipping the electric cables to the joists at 50% depth as the electric cables were not clipped at all

-Extending the lighting cable down through the ceiling in three places. For the first lighting cable extension I added a Hylec Debox 4 pole junction box (deskb-002-t) at 50% joist height to join two 1.5mm2 cables. Can I use this junction box or do I need something else?

 

[EFLImpudence]

-Clipping the electric cables to the joists at 50% depth as the electric cables were not clipped at all

It is not really necessary to clip them.
It can be argued that it is better not to.

-Extending the lighting cable down through the ceiling in three places. For the first lighting cable extension I added a Hylec Debox 4 pole junction box (deskb-002-t) at 50% joist height to join two 1.5mm2 cables. Can I use this junction box or do I need something else?

No - you need a "Maintenance free" junction box.

One example: https://www.tlc-direct.co.uk/Products/ASJ804.html

 

[TryAgain1]

It is not really necessary to clip them.
It can be argued that it is better not to.


No - you need a "Maintenance free" junction box.

One example: https://www.tlc-direct.co.uk/Products/ASJ804.html

Are the Ashley J804 suitable for 1.5mm electric cables?

I also have about 10 pre existing (ie signed off by electrician) of 'Essentials 30A 3-Terminal Heavy Duty Junction Box Black' (https://www.screwfix.com/p/essentia...on-box-black/7552D?gad_campaignid=23271912844) already under the floor. These were not screwed to the joist which I intend to do. Hope these are ok?

 

[EFLImpudence]

Are the Ashley J804 suitable for 1.5mm electric cables?

Yes.

I also have about 10 pre existing (ie signed off by electrician) of 'Essentials 30A 3-Terminal Heavy Duty Junction Box Black' (https://www.screwfix.com/p/essentia...on-box-black/7552D?gad_campaignid=23271912844) already under the floor. These were not screwed to the joist which I intend to do. Hope these are ok?

Yes.

Screwing them to the joists and clipping the cable is one way of complying with the modern requirement for cable restraint although not required in the past.

 

[TryAgain1]

Yes.


Yes.

Screwing them to the joists and clipping the cable is one way of complying with the modern requirement for cable restraint although not required in the past.

Thanks. is the 'Hylec Debox 4 pole junction box' classed as not maintenance free ie can only be used inside an access panel (e.g. 1 gang plate and backbox)?

 

[EFLImpudence]

Thanks. is the 'Hylec Debox 4 pole junction box' classed as not maintenance free ie can only be used inside an access panel (e.g. 1 gang plate and backbox)?

Screw terminals and/or no cable restraints are not classed as MF.

 

[JohnW2]

I also have about 10 pre existing (ie signed off by electrician) of 'Essentials 30A 3-Terminal Heavy Duty Junction Box Black' (https://www.screwfix.com/p/essentia...on-box-black/7552D?gad_campaignid=23271912844) already under the floor. These were not screwed to the joist which I intend to do. Hope these are ok?

Yes.

Why are you saying that having non-MF JBs under the floor' is 'OK' - perhaps because there was no requirement for MF ones when they were installed?

 

[TryAgain1]

Why are you saying that having non-MF JBs under the floor' is 'OK' - perhaps because there was no requirement for MF ones when they were installed?

Yes

 

[JohnW2]

Yes

My question was actually directed at EFLI but, yes, that's the only reason I can think of for regarding it as OK.

It is generally true that changes in the regulations are not 'retrospective' although, at least in common sense terms, there is 'a limit' - i.e. there are things that were compliant with regulations when they were installed very many years ago that many/most people would not regard as 'acceptable' (or, at least, 'sensible'!) today