Cables behind skirting boards

[RobFurn]

Can someone clarify this its been bothering me;
522-06-06 (iii) of the regs states that a cable enclosed in a wall at a depth of less then 50mm shall be enclosed in earthed conduit or mechanically protected to prevent penetration of cable by nails, screws and the like.

If the cable was behind skirting board which is defo not 50mm should it be mechanically protected by earthed metal conduit as well? As the skirting board is wood anyone could drive a nail into it and penetrate the cable therefore its not sufficiantly mechanically protected. (maybe my interpretation of the mechanical protect bit is incorect here)

the other reason I question this is that skirting board is outside of the accepted safe zone quoted in 522-06-06 (iv)

 

[Adam_151]

522-06-06 (iv) applies regardless of whether or not there is a skirting board there or not

Of course if (iv) is not relevant to your situation then you must use one of the methods described in (i) to (iii) unless the cable is more than 50mm deep

I'm not sure I really understand the question

 

[Maxxy]

Are you talking about tucking it behind the skirting board, or in the wall behind the skirting board?

Either of these is not too clever. If its in the wall behind the skirting board, personally i would put it in earthed metallic conduit no matter what its depth, as theres just too much potential for it to get drilled through.

 

[sm1thson]

the other reason I question this is that skirting board is outside of the accepted safe zone quoted in 522-06-06 (iv)

i dont have a copy of the regs, but everything i have seen indicatet that the skirting is in a safezone. edit: i misread the meaning of safezone, (i though it was the areas inbetween the permitted routes where its safe to put nails etc) -clearly this is not the case.

the permitted routes (ie none safe zones) are:
-Zone within 150 mm of the top of the wall - see condition (iv)(a).
-Zone within 150 mm of an angle formed by adjacent walls - see condition (iv)(b).
-In a zone either horizontally or vertically to a point, accessory
or switchgear to which the cable is connected - see condition (iv)(c)
taken fom here

so top of wall and corners are permitted routes, not bottom of walls!

 

[RobFurn]

I guess all 522-06-06 part (iii) means is that you can lay your cable anywhere so long as its either protected by earthed metal conduit or protected by sufficient mechanical protection, my question really is does skirting board provide enough mechanical protect to satisfy the regs so you don't have to bother with metal conduit. Personally I think not.

 

[sm1thson]

given that it is perfectly normal to screw a skirting board into the wall -no!

metal conduate isnst suitiable mechanical protection, thats why it must be earthed, so i definately wouldnt class wood as been suitiable mechanical protection for stopping a nail!

 

[RobFurn]

Thanks just wanted to get other peoples opinions as I have seen cables behind skirting before without any conduit and always thought it was dodgy.

 

[Adam_151]

No a skirting board does not satisfy 522-06-06 iii)

 

[RobFurn]

sm1thson

you say in one of your posts that permitted routes are none safe zones.
What do you mean! surely premitted routes are by there very nature safe zones. Skirting is not in one of the listed zones so its considered unsafe and needs protection.

 

[sm1thson]

What do you mean!

yes my bad, i had mis read it, i thought there were permitted routes and safezones inbetween, ie i thought the safezones were where it was safe to put a nail, rather than safe to run a cable. oops.

 

[RobFurn]

cheers sm1thson thought I was loosing the plot for a min there

 

[SuperBob]

Can someone clarify this its been bothering me;
522-06-06 (iii) of the regs states that a cable enclosed in a wall at a depth of less then 50mm shall be enclosed in earthed conduit or mechanically protected to prevent penetration of cable by nails, screws and the like.

If the cable was behind skirting board which is defo not 50mm should it be mechanically protected by earthed metal conduit as well? As the skirting board is wood anyone could drive a nail into it and penetrate the cable therefore its not sufficiantly mechanically protected. (maybe my interpretation of the mechanical protect bit is incorect here)

the other reason I question this is that skirting board is outside of the accepted safe zone quoted in 522-06-06 (iv)

Can I just bump this one back to the top because I'd like to clarify please.

So we are basically saying that....You can't pull cable up from the floorboards,up behind the skirting,then into the accessory...unless the chase in the wall is at least 50mm?

Lets say for some reason you can't chase 50mm depth,would you have to wire from say the loft and chase all the way down?

Does anyone use steel galv sheathing? If so how do you earth it? Hole and ring crimp?

I'm a little confused,probably too much Christmas spirit Neither do I do much domestic work (you can probably tell )

Any answers appreciated.

 

[JohnD]

So we are basically saying that....You can't pull cable up from the floorboards,up behind the skirting,then into the accessory...unless the chase in the wall is at least 50mm?

No we aren't saying that.

A cable which is run directly vertically from a socket or switch is in a safe zone because, seeing the socket, you can be expected to be aware that it has a cable going to it, and not drill directly under it. The same goes for direct horizontal cables.

We are saying that a gap behind a skirting board must not be used as a duct to stuff cables into and run them around the room.

Read smithson's post, above, timed at Thu Jan 04, 2007 2:37 pm

 

[SuperBob]

Thanks very much John D.

That's cleared it up nicely for me.

 

[fatty]

What conduit can be used to run cables outside of a safe zone? What's the best way to earth it?