burried cables

[mick21]

Hi all
can someone please tell me is it in the regs that capping must be used when burying t&e cables in a plastered wall.
Thanks

 

[Amp David]

Don't think its a must, more a personal choice.

All capping does is protect the cables from damage until, or whilst being plastered.

It can make rewiring at a later date easier, as cables can just be drawn in.

 

[wallyanker]

Hi, just found this on the net, maybe of some help or maybe no help at all.

Regulation 522-06-06
A cable concealed in a wall or partition at a depth of less than
50 mm from the surfaces of the wall or partition shall:
(i) incorporate an earthed metallic covering which complies with
the requirements of these Regulations for a protective
conductor of the circuit concerned, the cable complying with
BS 5467, BS 6346, BS 6724, BS 7846, BS EN 60702-1 or
BS 8436, or
(ii) be of insulated concentric construction complying with
BS 4553-1, BS 4553-2, or BS 4553-3, or
(iii) be enclosed in earthed conduit, trunking or ducting satisfying
the requirements of these Regulations for a protective
conductor, or be mechanically protected sufficient to prevent
penetration of the cable by nails, screws and the like, or
(iv) be installed in a zone within 150 mm from the top of the
wall or partition or within 150 mm of an angle formed by two
adjoining walls or partitions. Where the cable is connected to
a point, accessory or switchgear on any surface of the wall or
partition, the cable may be installed in a zone either
horizontally or vertically, to the point, accessory or switchgear.
Where the location of the accessory, point or switchgear can
be determined from the reverse side, a zone formed on one
side of a wall of 100 mm thickness or less or partition of
100 mm thickness or less extends to the reverse side.

So basically if the cable is not in one of the acceptable zones and it is not more than 50mm deep, it needs protection, and capping does not provide protection.

 

[cbw]

There is no need or regulation requiring protection of T+E installed in correct areas.

My last rewire all went in oval conduit to protect from trowel damage by plasterers.(Personal preferance)

Did cost me about a tenner more on materials but at least I wont have to f*** about trying to replace damaged cables at a later date.

CBW

 

[mick21]

Thanks

 

[roukel01]

REG 522.8.1. A wiring system shall be selected and erected to avoid during installation, use or maintenance, damage to the sheath or insulation of cables and their terminations.


Now to me, that means use capping/tube unless its a new build and the walls are either i) stud walls or ii) dot and dab (I still put it in tube)

I for one, use oval tube every time, it looks more professional than clipping straight to the wall, its easy enough to do, gives it a bit of protection when other trades are working on the same building, and if you are ever called back to a burnt out socket, you have a fighting chance of pulling some slack down to do a repair.

 

[banny07]

no regs but it is a good practice

 

[padmore12345]

So basically if the cable is not in one of the acceptable zones and it is not more than 50mm deep, it needs protection, and capping does not provide protection.


'needs protection' doesnt mean by capping alone. it means protection by an rcd. so you can put cables into plaster direct , if protected by an rcd, its just not good practice. also even if cables are run in prescibed zones they still need protection by rcd unless run in earthed metal conduit or deeper than 50mm.

 

[dolomite]

As I understand it, if you do not protect the cable from the plaster then over time the cable will become brittle. I've been told the some of the materials, possible lime, in the plaster will eat away at the sheathing causing it to become brittle and then break down the insulation over time.
This might take years but always better to be safe than sorry!!

Hope this helps.

Dave

 

[Notsosmart]

As I understand it, if you do not protect the cable from the plaster then over time the cable will become brittle. I've been told the some of the materials, possible lime, in the plaster will eat away at the sheathing causing it to become brittle and then break down the insulation over time.
This might take years but always better to be safe than sorry!!

Hope this helps.

Dave

This is an urban myth; Plaster does not chemically attack PVC. Nor does cement, but due to the heat generated in the curing process; it is prudent to try & counteract this if possible.

 

[Steve D]

Hi, just found this on the net, maybe of some help or maybe no help at all.

Regulation 522-06-06
A cable concealed in a wall or partition at a depth of less than
50 mm from the surfaces of the wall or partition shall:
(i) incorporate an earthed metallic covering which complies with
the requirements of these Regulations for a protective
conductor of the circuit concerned, the cable complying with
BS 5467, BS 6346, BS 6724, BS 7846, BS EN 60702-1 or
BS 8436, or
(ii) be of insulated concentric construction complying with
BS 4553-1, BS 4553-2, or BS 4553-3, or
(iii) be enclosed in earthed conduit, trunking or ducting satisfying
the requirements of these Regulations for a protective
conductor, or be mechanically protected sufficient to prevent
penetration of the cable by nails, screws and the like, or
(iv) be installed in a zone within 150 mm from the top of the
wall or partition or within 150 mm of an angle formed by two
adjoining walls or partitions. Where the cable is connected to
a point, accessory or switchgear on any surface of the wall or
partition, the cable may be installed in a zone either
horizontally or vertically, to the point, accessory or switchgear.
Where the location of the accessory, point or switchgear can
be determined from the reverse side, a zone formed on one
side of a wall of 100 mm thickness or less or partition of
100 mm thickness or less extends to the reverse side.

So basically if the cable is not in one of the acceptable zones and it is not more than 50mm deep, it needs protection, and capping does not provide protection.

Isn't this reg all about 'additional protection' ? Basically saying that if it doesn't meet all of the above then it needs additional protection of a 30mA RCD.