Confused about Gaine

[BobDee]

Just picked up a leaflet from the local Brico that describes how to run cables in plaster. Quote:

"En cas d'une cloison non porteuse, toute saignée oblique est interdite les saignées droites sont autorisées dans les limites indiquées ci-dessus"

I take this to mean that in non load bearing partition walls, horizontal gaine runs are not allowed (except for short ones of no longer than 50 cms).

Does this mean that for load bearing walls, different rules apply?

Regs

Still learnin!

BobDee

[Nick Trollope]

[quote user="BobDee"]

Just picked up a leaflet from the local Brico that describes how to run cables in plaster. Quote:

"En cas d'une cloison non porteuse, toute saignée oblique est interdite les saignées droites sont autorisées dans les limites indiquées ci-dessus"

I take this to mean that in non load bearing partition walls, horizontal gaine runs are not allowed (except for short ones of no longer than 50 cms).

Does this mean that for load bearing walls, different rules apply?

Regs

Still learnin!

BobDee

[/quote]

I think that this says that oblique (as in \) runs are not allowed (as this is the case) and that straight runs are only permitted as shown above...

 

 

[BobDee]

Hi Nick,

The picture that goes with the text shows three vertical runs and one horizontal (50 cms max). Weldom is the brico responsible. I dont understand the non load bearing wall reference. Are there different rules for chanelling exterior walls? Logically there would be more stringent rules for cutting channels in supportive structures. Perhaps there are. Maybe someone can help on this one.

Bobdee

[Gluestick]

Nick:

One thing that is not obvious is how one connects sockets on a single dedicated circuit.

I gather they are "Daisy chained" but does this mean going back up into the loft/roofspace for each socket and then coming down again?

If horizontal runs in gaine are precluded, how else can they be conncted in confmity with the current regs?

My confusion is because simply, if up and down is the only allowed implementation, then it would be better to use a connecting box each time, rather than series-connect through the sockets!

[8-)]

[expat paul]

Hi,

I've just been looking at the same thing and found in "The Book"  

 L'installation electrique, page 90, distribution encastree dans les parols

"L'encastrement dans les murs porteurs n'est pas limite alors que dans les cloisons les regles sont plus strictes et reglementees"

I will still go for vertical runs, if only to avoid drilling in to the cable at a later date.

As for connecting sockets on a dedicated circuit, a French electrician told me to run a feed to a junction box above the room in the loft and then spur /star feed each socket from there.

Hope this helps, but I am not a qualified electrican, so seek pro advice if in doubt. 

 

 

[BobDee]

Hi Paul. That sounds really what I was after. So.... if I want to fit two wallights on a load bearing wall, I can feed one from above or below vertically and then run horizontal gaine between the two.

I still dont see the logic in different rules for partition walls. Maybe the theory is that if you find a partituion wall in ten years time you should be able to assume that all the cables run vertically.

Regs

 

BobD

[jxedwards]

Chaps,

See comments below in Blue. I am basing my info on my 25 year old UK electrician qualifications and what I have ‘discovered’ re French NORMS. By no means definitive but I hope the comments help.

Note written before additional comments by BobDee. Bobdee no way Jose horizontal between lights big big no no.

I take this to mean that in non load bearing partition walls, horizontal gaine runs are not allowed (except for short ones of no longer than 50 cms). This is correct, also diagonal runs are a big No No. Recent case in the UK which finally prompted legislation was when a lady got electrocuted drilling a hole in her new kitchen wall. The person who had revamped the kitchen had installed the 6mm2 cooker cable diagonally across the wall with no mechanical protection under the plasterwork and incorrectly earthed. The regs/NORMS apply common sense if you have a socket/switch then you assume that it is fed vertically and no other way. Short 50 cms runs are allowed. This should apply to any wall load bearing or not, think about it.

My confusion is because simply, if up and down is the only allowed implementation, then it would be better to use a connecting box each time, rather than series-connect through the sockets! Probably however any connection in any circuit can be cause of a breakdown. Remember French NORMS require that access is available to all JB’s (junction boxes/boite de deviation). Therefore if you were to put JB’s in the ceiling/floor space above a room the JB’s would need to be accessible. If you series connect as you say at the socket then yes you use extra cable but all you connections are accessible.

To conclude if you are struggling with any of these concepts (and by the questions you have asked I would surmise so) then leave this type of work alone and hire a qualified person. Electricity is the silent hidden killer. As some would have noted from my previous posts on similar questions, if you screw up your plumbing connections you will get wet/furniture ruined/expensive. However unless you are laying on the floor unconscious the probability of death/serious injury is almost zero. Screw up electricity…..brown bread, goodnight Irene, hello pearly gates (maybe).

I am undertaking the rewire of our property myself. However when it comes to the relocation of my distribution board/tableau I will ‘contract’ this out to a fully registered French electrician as this task is beyond my knowledge of the French/EDF connection systems. Don’t be offended by my comments just everyone needs to be made aware of the hazards of getting an electrical installation incorrect. Even though I ‘left’ the UK domestic electrical industry 20 years ago I work in the offshore oil & gas industry with high voltage electrical systems so feel ‘qualified to comment thus.

Regards

John

 

[Gluestick]

Thanks John.

However:

Here is an earlier answer on another thread: http://www.completefrance.com/cs/forums/990785/ShowPost.aspx

[quote]

The rules for conduits buried in walls are quite complicated but If conduits are plastered into a wall - ie ; chased in, then maximum horozontal  run is 50cm.

Daisy chaining or repiquage as it is called in France is allowed for socket outlets and is indeed the usual way of wiring this type of circuit. [/quote]

Thus if horizontal runs, socket to socket is not allowed and the norm is up and down, surely, the optimal methodology is to use connection boxes rated at the circuit's full load, rather than inter-connecting between sockets?

If this approach is used, the supply cable from the tableau can be larger than the cables to each box (thus neatly balancing the load) and one avoids the final sockets taking the incremental load as the circuit progresses!

That was my earlier question.

Unless it breaks the Norm, then I would go for the alternative approach every time for the sake of a few additional circuit boxes.

[jxedwards]

Gluesstick,

Not sure about different size cable on a 'circuit'. Not good practice and not something i would do. Within the NORMS, no idea.

Nothing wrong with JB's feeding sockets from above however as I said they will need access and again not something I would do. No load at the socket as it is a direct connection and the cable being used should be capable of full circuit current.

Off the record I have run socket wires behind plasterboard horizontally at skirting board level. Against the NORMS/regs, yes. I know about them. Yes if I sell!!!! The big one is running horizontally/diagonally across walls where anybody could try and nail/screw anything, whoosh bang bang.

 

Bon chance

 

John

[BobDee]

Many thanks to John and GS for the responses.

John, or anyone, is there a separate case for LOAD BEARING walls? Are the norms or regs different here?

I am not a qualified electrician but have been in the professional electronics / computer /radio engineering  industry for many years and do understand the dangers that could be encountered. Never did understand though, how plastic trunking of even less gaine can protect against the uninitiated drilling blindly into walls. 

Resolved to ask the guys at Weldom next time I'm in town about horizontal runs. Does anyone know of an inspection that has failed because of this? Looking at some of the earlier posts, there's quite a few folk who it would seem, would benefit from firm clarification on this.

 

[Gluestick]

[quote user="jxedwards"]

Gluesstick,

Not sure about different size cable on a 'circuit'. Not good practice and not something i would do. Within the NORMS, no idea.[/quote]

Indeed a good practice, electrically!

If the load is x and the cable is fully loaded to x then the voltage will drop the further along the circuit you go, potentially.

By using slightly larger wire to feed from the tableau to the junction boxes, you improve the circuit's loading.

I'm sure Nick will eventually have some comments here: to which I look forward. Always a voice of theoretical authority and practical expertise.

 

[expat paul]

Thats just the way I did mine, after asking a French Reg sparky, I ran 4mm wires from the Tableau to the junction box and then star/spur feed each socket in 2.5mm from there. I also did a similar arrangement for the lighting circuits.

[Gluestick]

Makes lots of sense to me, Paul!

If one looks at French sockets and the tiny screws and the poor way they clamp the wire, the contact point resistance must be pretty enormous!

If one Daisy Chains say five double sockets, by the time the last one is reached, if some Bozo has plugged in three 2.5 Kw fan heaters early in the chain.................................

 

[Northender]

Surely the size of wire used will be pre-determined by the size of fuse chosen for that circuit?

For example if a circuit for 5 sockets is fused at 16A then there is no need for wire rated a 4mm , 2.5mm will suffice , unless of course we get into the area of voltage drops etc.for longer runs.

[Gluestick]

Which of course, we are, since my Grenier is over 30 M long....................... sans the ups and downs and rounds and abouts.

http://www.repereelec.com/index.php?page=edc

 

 

[BobDee]

OK, so no one can answer my original question. I'm sure thread hijacking is a Guillotinable offence!

BobDee

[Nick Trollope]

[quote user="BobDee"]

OK, so no one can answer my original question. I'm sure thread hijacking is a Guillotinable offence!

BobDee

[/quote]

I thort I did...

But, to answer your supplemental question, you can only; use horizontal runs of 50cm, you cannot; have diagonal runs or horizontal runs of more than 50cm. Therefore, all feeds to sockets (or wall lights), must be vertical, from above or below the socket/fitting. I assume that horizontal does not apply to feeds perpedicular to the socket (ie. through a thick wall),

That help? I'm afraid I haven't time to snswer everyone else's supplemental question. I would refer the honourable gentlemen to previous replies...

 

[BobDee]

Thanks Nick, but original question was:

"Does this mean that for load bearing walls, different rules apply?"

I'm still digging for firm information and it seems this question comes up all the time on French forums.

What I've learnt so far is that walls thicker than 10 cms do have different rules. The obvious allowed method for horizontal runs  is to get into the cavity of the bricks and and makes holes at every brick joint along the horizontal run to pass the gaine from brick to brick. You cant make diagonal runs or go over the top of doors or windows. Still not sure about laying gaine in plaster assuming its thick enough over the bricks so to do.

BobD

[Chancer]

My understanding is that the same rules apply re horizontal and diagonal runs of  gaines, however there are seperate normes regarding how much material can be channeled out  from a load bearing wall dependant on its thickness, I think nothing at all can be removed from 5cm briques alveolaires or carreau de platre.

I have found it best just to take the regs at face value, ie what they say, not what they dont say, a bit like saying to my difficult sister "you look nice today" to which she would reply " I suppose by that you mean that normally I dont!"

[Nick Trollope]

[quote user="BobDee"]

Thanks Nick, but original question was:

"Does this mean that for load bearing walls, different rules apply?"

[/quote]

Ah OK.

Well then, yes, the rules are basically the same for loadbearing walls, but you can't have any runs above a doorway. As JR says, this is about strength. You can't do anything that may weaken the structure. Bear in mind that you can't (or won't if you have any sense) build load bearing walls from plaster blocks or hollow bricks.