cables under suspended floor on dirt.

[1Justin]

1930's house with timber suspended ground floor over dry dirt. No depth for access. Existing ring final and radial circuits run under floor, and cables are thrown into the space, mostly resting on the dirt, maybe a clip here or there, but only usually for efffect where they perhaps get near an access hole and someone might have added one to make it look neater!

So if I am extending such a circuit(s), and need to add additional cable under the floor. - I own the whole circuit now.
A) I can't get the existing cables out of the dirt. I can't find what 17th would say about this.
B) I can't clip my new cables to joists because I have no access. Repeating the old method (throwing them in) feels wrong, although the cable would technically be mostly supported (by the dirt).

What to do? - And it will be inspected job for NICEIC.

Justin

 

[1shortcircuit]

Sounds like a 10 min job is going to be a 3 hour job

I agree, dry dirt. No room to get in and clip so that means the incline either end will not be great but just add a timber to clip and support as per the regs.

I'm all for making a job look neat and tidt but bu the time you have supported the first leg you could have had the entire ring/radial in situ.

Even if you were concerned about rodents chewing the cable on the ground, your rope, wire or tray will just add to their entertainment and still end up with the same result.

Put it in the hole, fish it out the other side, support the drop and the incline and move onto the next leg. You'll be there for hours otherwise:thumbsup

 

[Octopus]

You've got to ask yourself what the meaning of "support" is?

As outlined you have described an awful lot of houses in the UK and do we all tear up the floors to clip the cables to the base of the joists?

To me support, provided by a dry floor, is support.

Tin hat on.

 

[mackers]

just lay it on the floor and move on!LOL rope with cable tied to it wtf gonna look worse than on floor LOL

if not can't u cut a couple of traps or rip one floorboard up?

 

[nickjohn]

Surely the wire laying on the ground would be classed as supported and if it is under floorboards then it is protected from any form of mechanical damage, as far as rodents chewing they can get into stud partitions and do damage so no point worrying about under a floor..

 

[imago]

Just think of all the main bonding cables that would need clipping to joists if that became the requirement! IMHO the cable layed across the dry sub-floor is perfectly adequate. It's well out of the way of carpet fitters and plumbers, in a cool and temperature stable environment, and can be accessed only with tools. Rodents are the only likely threat to cable integrity there, and as has already been said, unless you use conduit that applies no matter what other system is employed.

If I'm looking at a job like this and I get one of those 'it doesn't look how I want it to' feelings then I just fall back on 'How can I improve this ?'. With this sort of job when you weigh up all the pro's and con's you can't improve on it IMHO. The only thing I'd do with this is to make sure the cables run neatly. i.e. along walls and in straight lines across the void, rather than criss crossed and tangled.

 

[leonard]

i can't see a problem with the cables laying under floorboards ,but if there is any problem for mechanical protection why not use flexible pvc conduit.

 

[Engineer54]

To be honest, i can't believe the suggestions made here, catenary wire, rope, wooden battens etc... So how are you going to clip cables to a batten (if you can get the length of batten in, ...in the first place) if you can't clip to the joists ?? Same with the catenary wire or rope, how are you going string it accross, let alone tie the cables to it...

This is taking regulations too literary, and not using your god given commonsense. It's a rod and fish exercise nothing more nothing less. Of course, you can always pull all the floor boards up, (Providing they haven't laid a laminate flooring down too that is) i'm sure the customer will just love that!!


Same thing when there is no loft access, rod and fish lighting cables, done that plenty of times with an electrician uncle i used to work with, long before i even started training...lol!!

 

[1shortcircuit]

Supported is supported whether it be resting on plasterboard or on dirt. My concern would be continuing such support when coming from dirt to socket so would probably insert a timber into dirt and fasten to joist when coming up to socket. Got one like this myself coming up about 2 foot gap, clutter galore beneath (Health and Safety says) I am not going in and if I am not prepared to go in then neither will I ask anyone else to go in.

I agree, dry dirt. No room to get in and clip so that means the incline either end will not be great but just add a timber to clip and support as per the regs.

I'm all for making a job look neat and tidy but by the time you have supported the first leg you could have had the entire ring/radial in situ.

Even if you were concerned about rodents chewing the cable on the ground, your rope, wire or tray will just add to their entertainment and still end up with the same result.

Put it in the hole, fish it out the other side, support the drop and the incline and move onto the next leg. You'll be there for hours otherwise:thumbsup

To be honest, i can't believe the suggestions made here, catenary wire, rope, wooden battens etc... So how are you going to clip cables to a batten (if you can get the length of batten in, ...in the first place) if you can't clip to the joists ?? Same with the catenary wire or rope, how are you going string it accross, let alone tie the cables to it...

This is taking regulations too literary, and not using your god given commonsense. It's a rod and fish exercise nothing more nothing less. Of course, you can always pull all the floor boards up, (Providing they haven't laid a laminate flooring down too that is) i'm sure the customer will just love that!!


Same thing when there is no loft access, rod and fish lighting cables, done that plenty of times with an electrician uncle i used to work with, long before i even started training...lol!!

I think you've misunderstood I know what I meant

The cable gets fished from one end to the other, rests on the floor the entire length of the run BUT gets supported on entry and exit by a small batten vertically/diagonally positioned so that the cable remains supported from the dirt to where it goes up into the wall behind the skirting board thus continuing SUPPORT :thumbsup


Try and fit a timber in lmao, you'd have to cut the bloody floor in half lol

 

[ash_s3]

To avoid the problem entirely IMO, why not just use pre-streched polyester braid (or dyneema if we want absolutely no stretch). Would be safer and much easier to work with than steel cable anyway. Leave a little slack, strap on the cable ties every~250mm, (or use heat-shrink tube straps), pull it in, tie it off both ends.

- And why not? - Have I just fixed my problem?

Justin

Wouldnt like to be paying you bill at the end of the job! Few extra sockets is starting to turn into a few days work. NIC man isnt going to be lifting floorboards surely?