Socket Wiring Advice - Part Dux!

[nero44]

Onto the next...

I am getting new flooring put down in my bedroom and as such I will need to strip the existing carpet down to the original floorboards. Whilst I have access, I want to wire a new socket onto the existing ring final and potentially cleanup a few things given that these areas will be inaccessible for a long time.

I've attached a quick sketch on the setup. Entrance door is on the bottom right and wires enter into the room under floor from the landing. I've also indicated how joists are running. Socket 1,2 and 3 are existing ones. 1 and 3 are on the ring main and socket 2 is spurred off socket 1. All sockets are currently in the skirting boards, but I will move them into the wall at the same time. The additional socket is planned for location four (to have a socket on each side of the bed). This is a three part question:

1. Should I spur off 3 to connect socket 4? Easy wiring and just one extra cable w/out any JBs. Or should I extend the ring to 4, which means I need to add a JB to extend one leg to go straight to socket 4. This then of course is difficult to reach once the new floor is down. JB for me would be wago221 with matching box, closed with zip ties...
2. Exact location of socket 4 >> there is a bathroom in the adjoining room. The walls are lath and plaster with vertical joists/studs. The location where I was thinking of putting the socket is actually exactly in between the same studs that have the shower mixer installed going out on the other side. This means in between the studs I have water pipes running up to the mixer. I am assuming the best answer here is to put the new socket in the gap space between the studs before the one holding the plumbing parts so they do not co-exist in the same space?
3. Since I have access to the floorboards, was wondering if it makes sense to replace some of the 30 year old cable with fresh T&E? Not sure yet how feasible this is as there are surprisingly not many JBs I could find, so where possible everything has been wired in one run. So I could in theory replace the cable between socket 1 and 2 and the one going to 3, but everything leaving the room is part of a much longer run. Then again is it worth it if there are actually no issues? The only thing I might consider is to add socket 2 correctly to the ring, by just joining two cables next to socket 1, but then again I have an unreachable JB under the floor and I always thought it is good practice to avoid JBs, cable splits etc. if possible.

Any views are greatly appreciated.

 

[Murdochcat]

If you want to have connections under the floor then you need Maintenance Free connections

The better solution would be to remove the cable from 1 to 3, add a cable from 2 to 4 and another from 4 to 3 - and properly test it before the floor goes down. That way you avoid the issue with joints under the floor and have all the connections at the sockets only

 

[nero44]

The better solution would be to remove the cable from 1 to 3, add a cable from 2 to 4 and another from 4 to 3 - and properly test it before the floor goes down. That way you avoid the issue with joints under the floor and have all the connections at the sockets only

Ah that is indeed the much better solution, doing away with JBs completely. Thanks for that.

 

[SUNRAY]

If you want to have connections under the floor then you need Maintenance Free connections

The better solution would be to remove the cable from 1 to 3, add a cable from 2 to 4 and another from 4 to 3 - and properly test it before the floor goes down. That way you avoid the issue with joints under the floor and have all the connections at the sockets onlyI

I did the sketch before preparing dinner and forgot to post it, oh well better late than never.

 

[nero44]

ahh love it when one project organically growths into five... while I have access to the floor... unrelated follow-up question:

The lower left corner of this 1st floor bedroom (so the area between socket 1 and 2) sits above my front door entrance. I currently have battery operated PIR lamp, but I would like to have a hard wired one, as the battery runs out every 6 months. The middle of the room sits above my reception room, which has a standard ceiling rose. I suspect this ceiling rose is loop-in wired and will be at the beginning of the loop (i.e. no free slot in the terminals.

My question is, could I just spur off the ceiling rose and squeeze a second TE wire into the "pass-through" terminals and just route the cable from the middle of the room down to the lower left corner? I would then need to install a ceiling rose in my doorway and find my way to the closest switch and swap a 1 gang for a 2 gang.

According to the latest EICR, the circuit has a 1.61 Zs with a maximum permitted 7.28 as on a 6a RCBO.

 

[ericmark]

According to the latest EICR, the circuit has a 1.61 Zs with a maximum permitted 7.28 as on a 6a RCBO.

This is the problem with DIY, I looked at replacing my loop impedance tester, even this cheap one, is around £70, I have hinted, and waiting for Father Christmas and see what I get. There are socket testers for radial circuits, but they pass at around 1.9Ω so not really any good for a ring final.

The problem is ensuring no wire springs off when working in a tight space, a loop impedance reading before and after should show all OK, but the accepted method is to test at the consumer unit, and most homes have the isolator in the consumer unit so no way to isolate before opening it.

Lights either work or don't work, and all we are worried about is if the earth is connected, the ring final may work, and it may have a good earth, but need to ensure it is still a ring final, and not two radials.

In real terms my ring finals are never loaded anywhere near their maximum, my whole use today is 3.4 kW well under the rating for the ring, I suspect most homes are the same, to get over 20 amp is rare, however you have to cater for those rare times, your outside with leaf blower, the washing machines are on, and then wife also turn on a kettle, it happens.

So you need to ensure all three cables line, neutral and earth are still part of a ring final, if you can't test, it is simple, don't do the job. Or at least be very very careful that no wire has become disconnected. Specially if using maintenance free stuff, which if you do find a fault latter is going to be a real problem getting access to it.

 

[nero44]

After spending a weekend ripping out the old flooring and dismantling 3 large wardrobes, I finally got to work on this. Hit a roadblock though… whilst moving socket 3 out of the skirting board and over to the right closer to the door, I found that the void between the studs is completely filled with plaster leftovers…I’ve only seen it fill up a few centimeters but this one appears to load up at least 45cm but probably much more… it will be impossible to get two wires through there…

Any ideas what todo? I dont want to move the socket too far in, as it will end up behind the backboard of my bed. If i move it just slightly over and then use a metal backbox going straight onto the stud, then i could possibly see if the void on the left is more manageable and have the wired enter the backbox from the left side? Plaster+laths is about 30mm deep, so tight fit but theoretically possible. Any issues with fixing a backbox onto a stud?

 

[Taylortwocities]

Any issues with fixing a backbox onto a stud?

No, assuming it is a stud and not a lath. As well as screwing it in, throw in a dob or two of fast set mortar. Its wont ever move again..

 

[SUNRAY]

That kinda looks like breeze/cinder block to me, are you sure it's loosefill?

 

[securespark]

Are they horizontal strips of timber?

 

[JohnW2]

Are they horizontal strips of timber?

I imagine they are probably laths (with 2, maybe 3, having been cut out ...

..... Plaster+laths is about 30mm deep,

 

[nero44]

That kinda looks like breeze/cinder block to me, are you sure it's loosefill?

Yup, I can poke around with a screwdriver and move stuff.

I cut out the middle lath hoping it was just a thick layer and it will all fall off inside the void.. but no chance unfortunately. I've already finished the new socket 4 the same way and it worked perfectly fine.

What would you think is the best way to close this hole again? I have drywall screws and can fix some support laths behind, but I do not have any dry wall to close and decorate.

 

[Taylortwocities]

Easyfill is good. But depends on the size of the hole to be filled.

 

[SUNRAY]

Yup, I can poke around with a screwdriver and move stuff.

I cut out the middle lath hoping it was just a thick layer and it will all fall off inside the void.. but no chance unfortunately. I've already finished the new socket 4 the same way and it worked perfectly fine.

What would you think is the best way to close this hole again? I have drywall screws and can fix some support laths behind, but I do not have any dry wall to close and decorate.

Have you tried poking downwards to see if you can force a cable route.
If the plaster lumps really are loose I'd have a play with the vacuum cleaner with the metal curved pipe and keep jabbing it into the plaster to try to break into smaller lumps and clear a path out, or try a long masonary bit.

 

[nero44]

A bit.. seems quite dense and I don't want to break the edges around the cutout, so my leverage is limited. I don't really know how high it piles up, so even if I start removing bits with the VAC, more pieces might just fall down further. Long masonry drill bit might be an option, but I just have no good angle/leverage to get down there without causing much more damage to the already brittle lath and plaster.

Will try again on the weekend. Mounting to the stud seems easiest, but also just realised my socket has USB ports, so it's a really tight fit. It just about fits inside a 25mm metal backbox without any wiring. I supposed it is not advisable to carve out another 5mm of the stud so the box has a bit more space?