522.6.6 & definition of a cable, and mods for a newbuild

[JohnW2]

Like cables concealed <50mm. must be RCD protected - automatically makes DIYers think "I must go deeper".

Quite - and, in any event, I'm far from convinced that 'just over 50mm' is particular safe. Most masonry drills are considerably longer than that, and it's far from unknown, if they hit fairly soft material, for them to suddenly 'go in' almost to their full length.

Kind Regards, John

 

[securespark]

"I must go deeper".

Oooh Matron!!

 

[SimonH2]

I'm far from convinced that 'just over 50mm' is particular safe. Most masonry drills are considerably longer than that, and it's far from unknown, if they hit fairly soft material, for them to suddenly 'go in' almost to their full length.

Indeed, and if I'm putting up something substantial (like shelves) then I'll most likely be using screws longer than 2" - and push the wall plugs in deeper than the plaster.
Here there's about an inch of bonding before you reach anything substantial (which unfortunately is "'kin 'ard" brick) so I reckon you need at least 2 1/2" to get a decent hold AND be sure that the weight is on the wall and not the (loose) plaster. Up at Mum's, some of the walls are very light block - the sort you don't need a drill for they are that soft. In those blocks, I'd be using 3-4" screws so as to get in deep and get some grip on the plugs.
But I do also wonder if we've perhaps gone too far now - or at least disproportionately far ? As I mentioned, at the same time as we have all these regs about buried cables, where they can be run, protection for them, and so on - the plumbers were running gas pipes where I think no-one would expect them, and don't tell me that an "average" DIYer won't just push/bash harder if the drill or nail meets a bit of an obstruction ? And while I suppose hitting a radiator pipe isn't a safety issue, I can imagine some swearing when on of those gets hit

 

[JohnW2]

But I do also wonder if we've perhaps gone too far now - or at least disproportionately far ?

One can at least question the effectiveness of the regulations.

We are agreed that ">50mm deep" in no way guarantees that a cable will not be hit by a drill. Furthermore, the fact that 'safe zones' exist does not guarantee that there are no cables outside of safe zones, no matter when the wiring was installed (or one thinks it was installed). One therefore has to be vigilant (i.e. do one's best to confirm the absence of buried cables or pipes) whenever one takes a drill or nail to a wall, even if it is outside of 'safe zones'.

IF we are to have such regulations then rather than "too far", I would suggest that it could well be a case of "not far enough". If we feel that buried cables deemed to be 'at risk' should be RCD-protected (or in conduit, earth-sheathed cable or whatever), then I think (for the reason we have agreed), that requirement probably should apply regardless of the depth of the cable. In practice, that wouldn't make much difference, since it is rarely practicable to bury cables much more than 50mm deep, but at least the reg would then make more sense.

Kind Regards, John

 

[SimonH2]

One therefore has to be vigilant (i.e. do one's best to confirm the absence of buried cables or pipes) whenever one takes a drill or nail to a wall, even if it is outside of 'safe zones'.

It's been something of an education seeing these new houses, and finding where the gas pipes run in my rental house. I just find it amazing that the gas business has no such rules. But at least in my rental house, the water pipes are copper - in the house Mum is looking at they are plastic.
There is what looks like a metalised tape behind the pipes, though I assume that's as a heat reflector - I think I might take my metal & stud detector with me next time I have to go there and see if it can pick anything up.

If we feel that buried cables deemed to be 'at risk' should be RCD-protected (or in conduit, earth-sheathed cable or whatever), then I think (for the reason we have agreed), that requirement probably should apply regardless of the depth of the cable. In practice, that wouldn't make much difference, since it is rarely practicable to bury cables much more than 50mm deep, but at least the reg would then make more sense.

I'm inclined to agree - and if you are burying cables more than 50mm deep, it's unlikely that using metal conduit would be much more of an inconvenience.

At some point I'm going to have to go and talk to the vendor myself. I suspect he's thinking that if I want to put network cables in, I'll have to do it myself - but I'm very much leaning towards not creating a situation where the builders can try and wriggle out of any problems because "I must have caused it". It's going to be a b'stard of a job to do anyway. It might be possible to fish up behind the dot-n-dab, but the ceilings are all in and plastered, as is the "glued together so it's one big mass" floor, and some of them will have to get from back to front of the house - no attic as that's all fully boarded and plastered as a bedroom, shower, and storage.

Looking at it, it's hard to imagine anything more perfectly designed to be non-maintainable.