Capping off electrics

The swiitch is no problem, just insulate & make safe the wires with a piece of connector block and fit a 1 gang switch. 
The cables in the wall are a different matter, ideally you should disconnect them from the circuit. If you're leaving them in place you should fit a blanking plate so show that there are cables there.

 

You'd need to trace them back, I suppose they run under the floor of the room above? If it's an upstairs room or a bungalow though you could just cut them off in the loft and put a small junction box on the ends. Of course they will be dead anyway once disconnected from the switch but they should be isolated as the earth and neutral will still be connected so if there's an rcd in circuit there will be a tripping problem if anyone drills or knocks a nail in them! There is one other possibility, if the loop-n has been done at the switch the neutral will be there so you could isolate the L+N from there, quite unlikely though I would think.

 

Surely if you disconnect them from teir supply and cut them short so the won't be reconnected for no good reason, you can then just fill over ?

Mr. HandyAndy - Really

 

Some years ago , me and a mate knocked through a wall to install a double door. Got one of those Super Saws (electric) which cuts through blockwork like a hot knife through butter. Nothing showing either side of the wall to indicate any wires etc so I did the vertical cuts and my mate did the horizontal cut. He only got about 1/4 of the way along when "BANG" he'd hit a hidden cable. I reset the electrics, he went along about another 4 ft when "Bang" hit another cable. Turns out, there had been wall lights up some years before. Cables had been screwed into conn blocks and buried in the wall (still live). We had to get a sparks in to trace and disconnect them.

 

That's the idea of the blanking plate Freddy.

 

Yes, EVERYONE needs to know that they are there.

But still, disconnectedfrom their supplies and cut short, I can't think why they should not be filled over and forgotten about.

Mr. HandyAndy - Really

 

Agreed Handy that would be fine but maybe he can't get at their origin without major disruption, eg carpets, sheet flooring, tiles etc.

 

If you really can't disconnect them from the supply and dont want **** looking blank plates in the middle of the wall, why not put the blank plate at socket height and in line with old light with a note saying what it's there for. However, disconnection is the safest way really.

 

Just rip the flamin cables out to ceiling height and stick small JB's on ends and then push up through the ceiling into floor void above. Make good and jobs done..flamin capping orffffffffffff cables and stuff..