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'Recessed' back box?

He presumably never encountered dimmers, smart switches, smart sockets, flat-plate accessories, sockets with USB chargers built in, Euromodules.....
I imagine that he probably retired before most of those things existed (or, in some cases, were even dreamed of!). As I said, he died recently, in his (very late) 90's.
 
Two potential concerns spring to mind.
1. Electrical conductivity. An electrical enclosure should ideally be made out of either a good conductor and connected to earth or made out of a good insulator. A material that is neither a good conductor or a good insulator poses a risk in that it may carry enough current to give someone a shock, but not enough to blow a fuse/trip a breaker.
I suppose one can't argue with that as a theoretical 'concern', but "scraping barrels" comes to mind.
2. Fire resistance, electrical enclosures are supposed to be made of flame retardant materials.
As you go on to say, masonry and plaster presumably qualify as 'flame retardant' ? (but I'm not at all sure about the material that plasterboard back boxes are made of).
..... neither a good conductor or a good insulator .....
Beware of the Grammar Police, who seem to patrol this forum ;)
 
... except, as you say, it's perfectly acceptable to send the devil away by sinking the 25mm box below the surface!

Whilst I essentially agree with your view, a real 'old-timer' electrician I knew, who died quite recently, in his 90s, used to say that anyone claiming that 25mm boxes were not deep enough "did not deserve to be called an electrician" ;)
But surely, in the 50s and 60s, only 35mm boxes were used for sockets (they were often those MK or MEM sockets which were chunky at the back; and 16mm boxes for light switches (no one ran neutrals to switches much in those days).
I thought 25mm boxes only came out around 1970, when sockets were made slimmer at the back.
 
But surely, in the 50s and 60s, only 35mm boxes were used for sockets (they were often those MK or MEM sockets which were chunky at the back; and 16mm boxes for light switches (no one ran neutrals to switches much in those days). ... I thought 25mm boxes only came out around 1970, when sockets were made slimmer at the back.
That may well all be true - but he probably didn't retire until the late 80s, maybe later, so will have had a good few years experience of the 'new-fangled' accessories and boxes :-)
 
But surely, in the 50s and 60s, only 35mm boxes were used for sockets (they were often those MK or MEM sockets which were chunky at the back; and 16mm boxes for light switches (no one ran neutrals to switches much in those days).
I thought 25mm boxes only came out around 1970, when sockets were made slimmer at the back.
My initial thought was that is the reverse of my recolection, however as I mentioned earlier my father always got the cheapest item so potentially that containing less metal. The only early deep BB I was aware of was for the 6x6 cooker switch box.
 
My initial thought was that is the reverse of my recolection, however as I mentioned earlier my father always got the cheapest item so potentially that containing less metal. The only early deep BB I was aware of was for the 6x6 cooker switch box.
So, for an old style single socket, which required a 35mm box, he would use a 16mm box?
I bet the plasterers loved him.
 
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So, for an old style single socket, which required a 35mm box, he would use a 16mm box?
I bet the plasterers loved him.
very likely but diy, and making good himself, a little bit of helping others but not enough to get concered about
 
very likely but diy, and making good himself, a little bit of helping others but not enough to get concered about
What he saved on cheaper boxes, he put towards longer screws.
Didn't realise this was DIY and small jobs.
 
As you go on to say, masonry and plaster presumably qualify as 'flame retardant' ? (but I'm not at all sure about the material that plasterboard back boxes are made of).
Agreed well and truly.
 
Whatever size box you install for something you usually need to consider 1/ airflow - as in cooling, 2/ not inviting undue force from tight bends on cables, 3/ ease/difficulty when installing.
I`ve always taken the view that any metal backbox should end up with the edges not protruding past the finished surface and if buried below then no problem - the pedantic might say it can potentially leave some of the accessory back less protected from accidental mechanical damage to some extent but anything up to 10mm would never lose me much sleep though (and probably not 20, 30mm or greater either).
One thing I have never liked is those damned 16mm "plaster depth" boxes, even for a 1G1W switch, bah humbug! (yes I know that ACCY bricks or NORI bricks can be a right pain sometimes)
 
At least one property (and I believe a second) had no back boxes at all, just cut out a hole, drilled and plugged for long thin woodscrews, I assume one of the plastic drilling template thingies had been used.

In my home the original backboxes were wooden and many of then are still in use, in those days each accessory came with two 4BA screws and 2 wood screws.
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Whatever size box you install for something you usually need to consider 1/ airflow - as in cooling, 2/ not inviting undue force from tight bends on cables, 3/ ease/difficulty when installing.
(2) and (3) make sense - but as for 'airflow'. there usually won't be any in the case of a metal back box, will there? ... in which case I wonder what 'considering' you do about it?
 
At least one property (and I believe a second) had no back boxes at all, just cut out a hole, drilled and plugged for long thin woodscrews, I assume one of the plastic drilling template thingies had been used.
I inherited some of those in my home - and some actually 'worse' - woodscrews into the laths of a lath and plaster stud wall
In my home the original backboxes were wooden and many of then are still in use, in those days each accessory came with two 4BA screws and 2 wood screws.
..and I also inherited a few sockets on skirting boards, which were just screwed on over a hole in the skirting. Mind you, they were massive Victorian skirtings - about 12" x 3" and 'hollow", so the face onto which the socket was screwed was only about half an inch thick, with plenty of 'open space' behind.
 
Those wooden back boxes were basically the “standard” once upon a time not ideal by modern regs, but they certainly did the job for decades.
Indeed. I'm not actually sure that, in electrical terms, they are really significantly 'not ideal'.
 
I inherited some of those in my home - and some actually 'worse' - woodscrews into the laths of a lath and plaster stud wall
I haven't seen them in lathes myself but you are not the first to mention it
..and I also inherited a few sockets on skirting boards, which were just screwed on over a hole in the skirting. Mind you, they were massive Victorian skirtings - about 12" x 3" and 'hollow", so the face onto which the socket was screwed was only about half an inch thick, with plenty of 'open space' behind.
Yes yery common I believe
Indeed. I'm not actually sure that, in electrical terms, they are really significantly 'not ideal'.
Electrically I don't have an issue with them, of course the fire resistance raises doubt with some but my biggest gripe is the lack of space, in our dining room there is a dimmer which is terrible, it starts flashing at significantly below full power but I can't find anything else that will fit in the wooden box.

I went down Erics route, to the point I got a 10W RGB LED bulb with 16 button remote control.
Mrs Sunray quickly said: "Not another bl@@dy remote control" and several months later having to change the 2025 for a second time and not being able to turn the light on...
 
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