Sealing exposed live wire

[K-Lye]

Hi all.. I'm not an electrician by profession but not above doing any basic work that doesn't need qualification. I've got a scenario currently where I'm installing a new light switch - it's an fully enclosed unit with the terminations on the rear which leave part of the wires exposed where they terminate. Once mounted, this will be within the wall cavity of the stud wall where it's being installed. Not a real problem in itself but I prefer things to be done as best as possible so looking to dab so electrical sealant on the exposed wires (once fully terminated) to ensure they're fully insulated.

So here's the question - I know you can buy specialist electrical sealant but I believe that's industrial grade stuff and a bit overkill for the standard domestic 240V. I spoke with the local electrical specialist down at our B&Q who said normal silicon sealant would do the trick. That seems consistent with advice I've read online but I wanted to post here and get some expert views.

Thanks!

 

[Darkwood]

Sorry but electrical specialist and B & Q dont go together, i cant really understand what your trying to do here as any light fitting termination should be in some sort of enclosure, sealing exposed terminations with setting sealant stops them been available for inspection etc ... it might seem like a small job but done wrong can be a fire hazard if not electrical risk.

Ps Electrical specialist (B&Q) should be in the joke section, do you honestly think hed be working on minimum wage if he was such an expert????:saddam:

 

[nickblake]

Sealing exposed wire , if the back box is a patress or metal back box thats earthed and the termination has been done to a good standard then there is no requirement to seal with sealant or any other adhesives this will just cause problems if the switch has to be replaced

 

[mechelec]

if this isnt a wind up (Band Q electrical specialist my ar*se) then I would say dont use standard silicone sealer on electrical accessories. It contains acetic acid and causes corrosion on terminals epecially in enclosures where the acetic acid condenses and has no where to escape.

 

[Marvo]

If the light switch has a BS or ISO standards mark on it and the wire is correctly prepared and the termination is made correctly then there shouldn't be a need to insulate anything after the termination is made. Don't apply any sealant or insulating material from a tube onto the connections, it's going to cause havoc in future and silicone is likely not to stick very well anyway.

If you can attach a photo of the back of the switch with the wires terminated maybe we can advise you better.

 

[Darkwood]

I suspect the OP may have a dry-lining box (plasterboard recess box)... can you confirm what type of back box you have??

 

[K-Lye]

Haha! Re. B&Q.. thought you guys would find that amusing

Fire hazard is exactly my concern hence why I'm here. So yes, here's a picture of the rear of the switch:


So as you can see it's exposed. I suppose I could buy a separate plasterboard box and sit this on top of it - the screw holes do appear to be in the right place but I can't imagine the switch was intended to be installed this way?

 

[Darkwood]

Haha! Re. B&Q.. thought you guys would find that amusing

Fire hazard is exactly my concern hence why I'm here. So yes, here's a picture of the rear of the switch:
View attachment 10444

So as you can see it's exposed. I suppose I could buy a separate plasterboard box and sit this on top of it - the screw holes do appear to be in the right place but I can't imagine the switch was intended to be installed this way?

Im getting the jist now you were planning on screwing this direct to cavity wall with no backbox... this is a NO/NO ... use a single socket size dry lining box and cut into cavity wall between joists thus all enclosed and done correctly.

 

[telectrix]

that switch is perfectly standard. as darkwood's post. fit a plasterboard ( dry lining box ) in the stud wall and fit switch.

 

[mechelec]

ffs be careful if you are going to play with electricity. Get an electrician in to do this for you properly as you have proved you have insufficiant knowlege to complete this work safely.
I only hope it is your own house you are trying to burn down not some unsuspecting customer.

 

[K-Lye]

Steady on mechelec.. the only thing I've proven is knowing where the limits of my knowledge end and how to consult before undertaking this kind of work. I know this forum gets a fair share of horror DIY stories but if I was genuinely so maverick I wouldn't be here discussing this with you and you forum colleagues would I?

The problem I have with setting in a backbox (and I've done plenty of these appropriately which have been inspected by an Electrcian) is the location doens't support a full size one. This is the location where I'd like to install it.



Any thoughts greatly appreciated.

 

[Darkwood]

This vital info would have been better as your opening post now we all understand your dilemma and obviously a dry lining box wont be the solution, what is the width of the available wall space and is this a stud-wall with a possiblilty to move around the corner into a dry-lining box ??

 

[Octopus]

Steady on michaelc.. the only thing I've proven is knowing where the limits of my knowledge end and how to consult before undertaking this kind of work. I know this forum gets a fair share of horror DIY stories but if I was genuinely so maverick I wouldn't be here discussing this with you and you forum colleagues would I?

The problem I have with setting in a backbox (and I've done plenty of these appropriately which have been inspected by an Electrcian) is the location doens't support a full size one. This is the location where I'd like to install it.

View attachment 10445

Any thoughts greatly appreciated.

What's wrong with the existing switch?

 

[nickblake]

looking at the picture then you should be able to get a full size patress on there it will be surfact but will be fine the switch thats there is approximatly half size of a normal switch if you want it flush then some carefull cutting out and installing the appropriate back box im sure it will fit

 

[mechelec]

If you can get a standard size switch installed then why not the back box?
Or can you get an architrave metal back box remove some plasterboard fix to stud and make good, then fit an architrave switch.