Joining cable under floorboards
Graham Jones
My plan to add a socket to an existing ring circuit is turning out to
be a major worry for me. This really should be something a competent
diy-er could do. But in order to do it correctly, therefore following
the regs, is turning into a nightmare.
I will need to extend an existing ring, so initally I just thought a
junction box under the floorboards is the easiest way. But then I find
that junction boxes are not recommended for use in non-accessible
places. I would say that under floorboards is non-accessible. So I
found that you could get maintenance free junction boxes. But then
after doing some more reasearch it seems that whether these comply
with the regs is debatable and who knows if these will do the test of
time. I don't really want to be the guinea pig!
So now I would like to attempt the "proper" way of crimping and then
heat-sheiding. But as I have never done this I would like some advice
on how difficult this actually is. Is this easy to get right first
time? Or is it somewhat of a skill that needs to be learned. I don't
mind buying the proper tools.
All this leads me to wonder about the existing junction boxes in my
house, all the lighting circuit is done with junction boxes, a few
other existing sockets also use junction boxes. Some are under
floorboards some are in the loft.
Should I worry about these? Has anyone ever found a junction box where
one of the screws has worked loose. Maybe I should replace them all?
The ones in the loft I can easily inspect and I would say these could
be classed as accessible. Other people here must have junction boxes
under floorboards, do you inspect them regularly, say once every 10
years?
Thanks for any replies that might set my mind at ease! (very difficult
actually)
Graham
Nightjar
...
> Should I worry about these? Has anyone ever found a junction box where
> one of the screws has worked loose. Maybe I should replace them all?
> The ones in the loft I can easily inspect and I would say these could
> be classed as accessible. Other people here must have junction boxes
> under floorboards, do you inspect them regularly, say once every 10
> years?
Yes I have an no I don't. When I have had to add connections to junction
boxes, I've never found any screws that have worked loose. Indeed, if
there was a problem, it was loosening them off after a decade or two.
However, I was pleased that there were no junction boxes under the
ground floor of one house I lived in when the river overflowed its banks
and filled the under-floor void.
Colin Bignell
Dave Plowman (News)
<d2b700ac-d56b-4542...@k22g2000yqh.googlegroups.com>,
Graham Jones <grahamj...@gmail.com> wrote:
> I will need to extend an existing ring, so initally I just thought a
> junction box under the floorboards is the easiest way. But then I find
> that junction boxes are not recommended for use in non-accessible
> places. I would say that under floorboards is non-accessible.
You say wrong. Under floorboards is ok for a JB - inaccessible means
plastered in etc.
--
*Shin: a device for finding furniture in the dark *
Dave Plowman da...@davenoise.co.uk London SW
To e-mail, change noise into sound.
David Robinson
> Hello,
>
> My plan to add a socket to an existing ring circuit is turning out to
> be a major worry for me. This really should be something a competent
> diy-er could do. But in order to do it correctly, therefore following
> the regs, is turning into a nightmare.
>
> I will need to extend an existing ring, so initally I just thought a
> junction box under the floorboards is the easiest way.
Running it from an existing socket, via existing trunking, is the
easiest way! ;)
What do the regs say about new sockets on existing circuits? Is anyone
interpreting them as requiring new cable runs to be RCD protected?
If you're doing minor work on an existing installation, I think you
have to use a bit of common sense IMO. I'm not saying that's
necessarily _right_ or _legal_, but if what you have is acceptable
(albeit not in accordance with latest regs), than extension should be
at least as good, and not make anything less safe, but I'm not sure
I'd worry about making the little extra bit _better_ than all the
rest.
e.g. ...
> All this leads me to wonder about the existing junction boxes in my
> house, all the lighting circuit is done with junction boxes, a few
> other existing sockets also use junction boxes. Some are under
> floorboards some are in the loft.
...so one extra one is going to make not-a-lot of difference.
> Should I worry about these?
Do you like to worry about things?
> Has anyone ever found a junction box where
> one of the screws has worked loose.
Yes, in our old house all screws in all light switches, socket backs,
and junction boxes were "lose" in that they could be tightened easily,
but not so lose that the wires would fall out. The wires could move a
little. All wires had been twisted together anyway, so it made no
practical difference at junction boxes. At light switches and sockets
backs, you would imagine that there could be a problem - but until
they were disturbed (by me) I saw none.
> Maybe I should replace them all?
You could. There must be millions of houses wired just the same
though. While thinking about it might cause you to lose sleep (a good
enough reason to do it maybe), has anyone heard of a junction box
causing a fire?
> The ones in the loft I can easily inspect and I would say these could
> be classed as accessible. Other people here must have junction boxes
> under floorboards, do you inspect them regularly, say once every 10
> years?
No. Also, if you're paranoid and you keep tightening them up really
tight every year, then after a few years the wires will snap under the
screws.
> Thanks for any replies that might set my mind at ease! (very difficult
> actually)
Oh dear!
I've re-wired my house to have no junction boxes under floor boards. A
few in the loft, but very easily accessible - fixed to joists, above
floorboards.
btw, if you search on here, you'll find a debate as to whether under
floorboards is "accessible" - i.e. if putting a JB there meets the
regs.
Cheers,
David.
js.b1
can work loose.
The best way of extending a ring is to break the existing ring and run
new legs to the new socket(s) - thereby integrating the sockets so as
to maintain a ring topology.
An easy way of having accessible JB, particularly for a central
lighting centre such as upstairs & downstairs lights, is to use a 1G
or 2G box with blank-plate just below the ceiling somewhere. That is
how I will migrate our 19 junction boxes (!), many of which are
broken, sheath terminated outside, not actually necessary (*) and all
those I found had loose terminals. The occasional flickering lights
which the UPS did not confirm were actually from bad connections
flashing over and old red polythene insulation actually turning brown.
* By not actually necessary I mean there is a JB above every ceiling
rose for loop-in wiring with just 1 cable dropping to the ceiling
rose; said JB are buried under 280mm of loft insulation now and (from
the stench) something else too.
John Rumm
>
> My plan to add a socket to an existing ring circuit is turning out to
> be a major worry for me. This really should be something a competent
> diy-er could do. But in order to do it correctly, therefore following
> the regs, is turning into a nightmare.
You are probably worrying too much!
> I will need to extend an existing ring, so initally I just thought a
> junction box under the floorboards is the easiest way. But then I find
> that junction boxes are not recommended for use in non-accessible
> places. I would say that under floorboards is non-accessible. So I
Depends on your interpretation of "non accessible". Under a floor where
all you need to is take out a couple of screws to re-lift a floorboard
is not really non accessible. Plenty of places have JBs installed under
the floor like this.
Under a floor where its going to have underfloor heating pipes installed
all over it and then a fully bonded hardwood floor installed on top -
might be more non-accessible. (although even then you are still often
only a stanly knife and a bit of new plasterboard away from access to
those from the other side!)
So in your situation, I would look to see if I can run a cable from an
existing socket first, rather than having an under floor joint. If you
can't then I would use a good quality junction box - make the screw off
well, and cable clip the cables in and out of the box for a few inches
to make sure they are supported and can't pull on the box.
> found that you could get maintenance free junction boxes. But then
> after doing some more reasearch it seems that whether these comply
> with the regs is debatable and who knows if these will do the test of
> time. I don't really want to be the guinea pig!
>
> So now I would like to attempt the "proper" way of crimping and then
> heat-sheiding. But as I have never done this I would like some advice
Crimping and heatshrink is ideal for joining two cables that you are
going to plaster over etc, its not a good substitute for a junction box.
> on how difficult this actually is. Is this easy to get right first
For a wire to wire joint, yup easy. Even with no experience. one
practice on some spare wire and you should be able to do it first time
every time.
> time? Or is it somewhat of a skill that needs to be learned. I don't
> mind buying the proper tools.
As long as you have a ratchet action crimper, its fairly straight forward.
> All this leads me to wonder about the existing junction boxes in my
> house, all the lighting circuit is done with junction boxes, a few
> other existing sockets also use junction boxes. Some are under
> floorboards some are in the loft.
Quite common - not much to worry about.
> Should I worry about these? Has anyone ever found a junction box where
Not usually.
> one of the screws has worked loose. Maybe I should replace them all?
I have found old ones where the screws are not that tight - probably
just due to the copper creeping a little over time. They were still
making a decent electrical connection though. The worst ones tend to be
where they are in circuits that frequently run near to their max load,
and are subject to repeated heating / cooling cycles. Here is the cables
are not well supported they can work loose.
> The ones in the loft I can easily inspect and I would say these could
> be classed as accessible. Other people here must have junction boxes
> under floorboards, do you inspect them regularly, say once every 10
> years?
I don't even know what is in this house yet, but have had JBs under the
floor in other properties. I have never formally inspected any of them,
apart from when needing to access one for some other reason.
--
Cheers,
John.
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Andy Dingley
> You say wrong. Under floorboards is ok for a JB - inaccessible means
> plastered in etc.
"Inaccessible" is relative. My usual approach is to try and make the
inaccessible accessible, by putting in a decent floorboard trap that I
can re-open in the future without major grief. For floorboards this
usually means a short trap near a corner, so that I can roll a corner
of carpet back and unscrew something, rather than needing to move
furniture and then lift a whole floorboard.
I'm considering one at the moment (wall penetration to outside lights)
where I'm going to sink a large galvanised box into the wall and make
a short trap in the skirting board over it. We're hoping to sand the
floor in there in a couple of years time and I don't want any chopping
of the boards if I can avoid it.
A Plumber
"John Rumm" <see.my.s...@nowhere.null> wrote in message
news:iLidneKpEbotAlzR...@brightview.co.uk...
Don't think you should do it unless you have part P certificate m8
ARWadsworth
> "John Rumm" <see.my.s...@nowhere.null> wrote in message
> news:iLidneKpEbotAlzR...@brightview.co.uk...
> Don't think you should do it unless you have part P certificate m8
Complete rubbish.
The socket is in a bedroom.
--
Adam
ARWadsworth
> On 22/10/2010 12:55, Graham Jones wrote:
>> Hello,
>>
>> My plan to add a socket to an existing ring circuit is turning out to
>> be a major worry for me. This really should be something a competent
>> diy-er could do. But in order to do it correctly, therefore following
>> the regs, is turning into a nightmare.
>
> You are probably worrying too much!
I agree.
<SNIP some good advice>
If you are really worried about a junction box then take the cable to the
nearest socket that is on the ring instead.
Cheers
--
Adam
Dave Plowman (News)
<7759f07e-7dc8-4527...@j2g2000yqf.googlegroups.com>,
Andy Dingley <din...@codesmiths.com> wrote:
> > You say wrong. Under floorboards is ok for a JB - inaccessible means
> > plastered in etc.
> "Inaccessible" is relative. My usual approach is to try and make the
> inaccessible accessible, by putting in a decent floorboard trap that I
> can re-open in the future without major grief. For floorboards this
> usually means a short trap near a corner, so that I can roll a corner
> of carpet back and unscrew something, rather than needing to move
> furniture and then lift a whole floorboard.
I doubt the regs are written for DIY types - most home owners wouldn't
have a clue where a JB might be under the floor - and that would apply to
an electrician brought in to sort any fault too.
But do you really need to make it easy to get to your own work? I've
never had connections in a JB fail.
--
*When the going gets tough, the tough take a coffee break *
Andy Dingley
> I doubt the regs are written for DIY types - most home owners wouldn't
> have a clue where a JB might be under the floor
RTFM. My house(s) have one. One copy is paper, the other is labelled
(where possible) on the wall or floor itself. There's a lot of stuff
pencilled under the wallpaper.
Bob Eager
Same here. The paper gives measurements from specified walls (X and Y).
The floorboards (not decorative) have large indelible circles/crosses
with the relevant junction box type and number beside them.
--
Use the BIG mirror service in the UK:
http://www.mirrorservice.org
*lightning protection* - a w_tom conductor
John Rumm
> "John Rumm"<see.my.s...@nowhere.null> wrote in message
> news:iLidneKpEbotAlzR...@brightview.co.uk...
>> On 22/10/2010 12:55, Graham Jones wrote:
>>> Hello,
>>>
>>> My plan to add a socket to an existing ring circuit is turning out to
>>> be a major worry for me. This really should be something a competent
>>> diy-er could do. But in order to do it correctly, therefore following
>>> the regs, is turning into a nightmare.
>>
>> You are probably worrying too much!
> Don't think you should do it unless you have part P certificate m8
Part P does not apply since this is a non notifiable activity.
--
Cheers,
John.
Dave Plowman (News)
<0308cd68-d2a1-43a8...@p26g2000yqb.googlegroups.com>,
Very laudable. I've done much the same. But as I said the regs ain't
written with the likes of us in mind.
--
*7up is good for you, signed snow white*
Fred
<din...@codesmiths.com> wrote:
>I'm considering one at the moment (wall penetration to outside lights)
>where I'm going to sink a large galvanised box into the wall and make
>a short trap in the skirting board over it.
Can you run cable behind skirting? I thought you weren't supposed to
in case someone nails the skirting through it but perhaps that's a
recommendation rather than a rule? I'm not suggesting you would
because you would know where you have fitted the box but a future
owner might not. OTOH it's not as if you are running it the length of
the skirting board, which increases the chances of a nail finding it.
Fred
<see.my.s...@nowhere.null> wrote:
>Depends on your interpretation of "non accessible". Under a floor where
>all you need to is take out a couple of screws to re-lift a floorboard
>is not really non accessible. Plenty of places have JBs installed under
>the floor like this.
When I first learned of this, I worried like the OP too. There seemed
to be conflicting advice here whether under the floor was accessible
or not but it seems this time round, pretty much everyone is happy
that it is accessible. I understand that many lights are wired from
JBs under the floor above (though I've never had any like this), so if
there was a problem nationwide, I think it would have been found by
now. This thread has reassured me too.
>Under a floor where its going to have underfloor heating pipes installed
>all over it and then a fully bonded hardwood floor installed on top -
>might be more non-accessible. (although even then you are still often
>only a stanly knife and a bit of new plasterboard away from access to
>those from the other side!)
Part of our kitchen has the tiled bathroom above. I'm wondering when
the time comes, would it be easy to rewire the kitchen by pulling the
ceiling off, rather than the tiles up!
John Rumm
The inventive sparky may be able to avoid either!
Fred
<see.my.s...@nowhere.null> wrote:
> I would use a good quality junction box - make the screw off
>well, and cable clip the cables in and out of the box for a few inches
>to make sure they are supported and can't pull on the box.
I was wondering about this. The advice with JBs is that the cables
must be clipped so that the weight of the cable isn't trying to pull
the wires out. If you are using the "keyhole surgery" method of
rewiring where you lift a board/make a hole in the floor the other
side of the room and use rods to lay the cable, how can you clip the
cable along its length?
I guess the important thing is to clip around the JB and you will have
access to that but don't the regs require clipping along the length of
the cable?
Thanks
Mike Clarke
> If you are using the "keyhole surgery" method of
> rewiring where you lift a board/make a hole in the floor the other
> side of the room and use rods to lay the cable, how can you clip the
> cable along its length?
I think the regs only require the cable to be supported, so a horizontal run
lying on top of the ceiling below (or even on the ground under the floor)
doesn't need to be clipped. Of course if the cable is in an accessible
position then it's good practice to clip it so it doesn't get disturbed.
--
Mike Clarke