cable chasing

J.C.E · Oct 26, 2015

Hi all

1st fixed a new extension for a mate of mines job on Saturday (hes a builder- works for his boss)
was my 1st job for him- so I wanted to please him and get him on side!

Ended up putting 2 sockets on the wrong wall (mutual mistake- I put sockets where the drawing showed them- but they sprayed to be on a different wall- which I missed! -not to much work to move them anyways

But He mentioned 'wheres the capping?'

-I explained capping isn't REQUIRED- my chases are a good depth- and cable is clipped back- and is to be plastered over- and all circuits are RCD protected

Then he went on to say 'not allowed to chase into block work now (guessing he meant breeze).....which I told him is aload of bull!

anyways- going back to move the 2 sockets tomorrow- am I right to stand my ground with the 2 above points

cheers guys

telectrix · Oct 26, 2015

you can chase into breezeblock, thermalite block etc. think there's a max. depth allowed vertical 1/3 of wall thickness, horizontal 1/6th.

J.C.E · Oct 26, 2015

and your personal views on use of capping?- more there just to protect from plasterer?

davesparks · Oct 26, 2015

Chasing into new blockwork is unnecessary, but not prohibited unless the structural engineer says otherwise.

Capping protects the cables from plasterers trowel and for most of is it's the way we were taught as best practice.

Leesparkykent · Oct 26, 2015

http://www.planningportal.gov.uk/uploads/br/BR_PDF_AD_A_2004.pdf

page 26

telectrix · Oct 26, 2015

walls are rarely plastered these days. it's all dot & dab. in which case there's no need for chasing and no need for capping.

tomspark93 · Oct 26, 2015

Sometimes capping is handy just to keep the cables in place but isn't required.

7029 dave · Oct 26, 2015

I like to use oval conduit, have done round conduit , socket and bushed for rewire purposes if clients want that.

Too Much Slack · Oct 29, 2015

We always use oval conduit, and screw it either side to hold it in place. Plus the installation its supposed to be rewireable

Darkwood · Oct 29, 2015

Too Much Slack said:
We always use oval conduit, and screw it either side to hold it in place. Plus the installation its supposed to be rewireable

This is not a requirement for future ease of rewires, some local councils may specify so, if you work for them.

shanky887614 · Oct 30, 2015

telectrix said:
you can chase into breezeblock, thermalite block etc. think there's a max. depth allowed vertical 1/3 of wall thickness, horizontal 1/6th.

like tell says, its in the electricians guide to the building regs.

if you are not allowed to chase a wall there are bigger structural problems.

if it was a 4' hole through a supporting wall i might have understood his concern.

capping isnt needed and doesnt protect the cables from the trowel anyway

sparksburnout · Oct 30, 2015

shanky887614 said:
like tell says, its in the electricians guide to the building regs.

if you are not allowed to chase a wall there are bigger structural problems.

if it was a 4' hole through a supporting wall i might have understood his concern.

capping isnt needed and doesnt protect the cables from the trowel anyway

you must have some flipping rough plasterers round there.

Midwest · Oct 30, 2015

davesparks said:
Chasing into new blockwork is unnecessary, but not prohibited unless the structural engineer says otherwise.

Capping protects the cables from plasterers trowel and for most of is it's the way we were taught as best practice.

Agree with davesparks, certainly way I was taught. OP why spend time chasing the wall anyway? If the wall is going to be plastered, the finished plaster depth, will cover cables clipped or cables covered in capping? Never liked burying cables in plaster, just don't seem right, like eating bugs!

Fox · Oct 30, 2015

Other than potential damage caused by a plasterer's float; what if the wall is going to be lined with thermal plasterboards that have the expanded polystyrene backs? PVC cables can react with the polystyrene over time. Fair enough if you're using new cable, but older cable is susceptible to insulation breakdown - a point worth thinking of if customers who are retrofitting existing buildings with existing, older wiring.

I'm coming across thermal boards more and more these days. Installing capping has always been cheap and quick, I don't see any reason not to use it and I always will do. By the time you've clipped cables to walls, you could have clipped capping to wall using same clips.