Electrician has created channels in wall for rewire. What do I fill in these channels with?

FrankFalcon

Hi all

A house I am doing up needs a rewire.  We have got a professional, qualified electrician doing the works in 2 stages.  He has now completed stage 1 and all wires are in the walls.  He told us...Fill your channels in with bonding, get your rooms reskimmed and we will be back when you need us to do 2nd fix.  So, when he says bonding, does he mean the grey stuff in a bag from B&Q or can I just use sand and cement (that I am already using elsewhere in the house)? 


Thanks

FreeBear

FrankFalcon said: He told us...Fill your channels in with bonding, get your rooms reskimmed and we will be back when you need us to do 2nd fix.  So, when he says bonding, does he mean the grey stuff in a bag from B&Q or can I just use sand and cement (that I am already using elsewhere in the house)?

This stuff -> https://www.british-gypsum.com/products/plaster-products/thistle-bondingcoat

Sometimes grey, sometimes pink. Good for filling deep holes and sticks to just about everything. Does have a tendency to crack as it dries if put on too thick.

You could use sand & cement, but apply some PVA or other bonding agent first. And make sure the cement is a milliletre or two below the original plaster.

Personally, I would have bedded the back boxes in with a dollop of bonding and used 20mm conduit for the cables rather than capping. Needs a deeper chase, but if the cables ever need replacing, much easier to pull new ones through.

moneysaver1978

I have used this https://www.wickes.co.uk/Knauf-Premium-Joint-Filler---10kg/p/224541 with success to fill deep gaps like yours (from removing door frames). I then finished with https://www.diy.com/departments/toupret-fine-finish-ready-mixed-finishing-plaster-1000g-tub/1849584_BQ.prd

grumpy_codger

I'm sorry for stating the obvious, but it's better to unscrew both sockets/faceplates before plastering and then fix them back, possibly even after painting.

MikeJXE

Yes take the faceplates off 

stuart45

The faceplates shouldn't be on if he's only done 1st fix.

35har1old

FrankFalcon said:

Hi all

A house I am doing up needs a rewire.  We have got a professional, qualified electrician doing the works in 2 stages.  He has now completed stage 1 and all wires are in the walls.  He told us...Fill your channels in with bonding, get your rooms reskimmed and we will be back when you need us to do 2nd fix.  So, when he says bonding, does he mean the grey stuff in a bag from B&Q or can I just use sand and cement (that I am already using elsewhere in the house)? 


Thanks

Should have used the correct conduit as the conduit would have been continuous to box.
The cable guard that has been used is more suited to surface mounting and even then there are better options available.
The aerial cable has no conduit at all.
There is also the possibility that the aerial cable has been connected so removal of the face plate may not be possible without disconnection.
TV points in the future will become redundant 

grumpy_codger

35har1old said:

FrankFalcon said:

Hi all

A house I am doing up needs a rewire.  We have got a professional, qualified electrician doing the works in 2 stages.  He has now completed stage 1 and all wires are in the walls.  He told us...Fill your channels in with bonding, get your rooms reskimmed and we will be back when you need us to do 2nd fix.  So, when he says bonding, does he mean the grey stuff in a bag from B&Q or can I just use sand and cement (that I am already using elsewhere in the house)? 


Thanks

Should have used the correct conduit as the conduit would have been continuous to box.

AFAIK, a conduit isn't compulsory now if a cable goes vertically or horizontally from a socket. It's just 'best practice'. Nobody in their right mind hammers nails or drills holes around sockets. And no conduit can stop an idiot from damaging a cable in a conduit.

The cable guard that has been used is more suited to surface mounting and even then there are better options available.

Better only because this one isn't for surface mounting.

The aerial cable has no conduit at all.

It doesn't have to, but would do no harm.

There is also the possibility that the aerial cable has been connected so removal of the face plate may not be possible without disconnection.

How come? The suggestions were to unscrew, not to remove completely, but even the latter can be done if needed.

TV points in the future will become redundant

And? In the future you can use a blanking plate instead or fill the backbox and plaster it over.

FreeBear

grumpy_codger said:

TV points in the future will become redundant

And? In the future you can use a blanking plate instead or fill the backbox and plaster it over.

If the coax had been in proper conduit, it would be a simple task to pull a length of CAT5/6 cable through. Then you could replace the aerial socket with an RJ45. But everyone is switching to WiFi, so even that would be redundant.

An alternative would be to link the double gang back box to the single with a short length of 20mm conduit. Then when the aerial connection becomes redundant, swap it out for a single socket and run a spur across to the double - Not too late to do that

rob7475

The capping is fine and as others as pointed out, not capping is needed when cables run in a line from an outlet. It's good to have it though as it protects the cable while you're filling the chase.

Those red bricks can sometimes pull the moisture out of bonding plaster causing it to crack so I usually get a couple of coats of 4:1 Water/PVA on the wall before I start. Let the first coat dry and get your bonding on when the second coat goes tacky. Try to get the bonding just below the surface level if you can. You can then use something like easifill or toupret to finish off which will blend easily into the surrounding wall. If you're having the whole wall reskimmed, just get the bonding level with the wall.

ThisIsWeird

FrankFalcon said:

Hi all. A house I am doing up needs a rewire.  We have got a professional, qualified electrician doing the works in 2 stages.  He has now completed stage 1 and all wires are in the walls.  He told us...Fill your channels in with bonding, get your rooms reskimmed and we will be back when you need us to do 2nd fix.  So, when he says bonding, does he mean the grey stuff in a bag from B&Q or can I just use sand and cement (that I am already using elsewhere in the house)?

Hi FF.

If you want to use sand-cement mortar 'cos you already have it, you can.

Are these sockets 'live'? If so, cut the power to them first, and try not to get them wet...

I'd be inclined to tape over that visible bit of cable as it enters to 'box, so's to not trap the cable, and also to not allow mortar to actually get into the box. Or, if the sparky has left any capping offcuts, cut one to fit.

Your walls look to be in generally good order? Were you planning to have them skimmed in any case? If so, just level off the mortar with the surface as said by Rob above. But if the walls don't otherwise need skimming, you can save yourself a good few £undred in each room by just filling these channels perfectly flush - again as Rob describes.