Vaulted Ceilings and safe zones cable routing

[mic2876uk]

Hello,

I know a safe zone for running cables exists 150mm from a corner or from a ceiling. I assume this still applies with a vaulted ceiling?

Meaning I can safely run cables within 150mm of where the ceiling starts to vault?

Although I guess for the gables i'll need to keep the cables within 150mm of the roof line?

 

[DetlefSchmitz]

It's one of those grey areas because it isn't specifically referred to. Tbh I would interpret in the most useful way, and not feel guilty.

Or, anything that isn't a wall must be a ceiling.

 

[sparkwright]

As above, if you think it's a wall, that's good enough.

 

[mic2876uk]

Great thanks guys,

The ceiling will be constructed as follows roof Tiles, membrane, air gap 100mm of insulation between the rafters 50mm insulation then plaster board.

In terms of running the cables in the ceiling where do they fit into that stack? I assume between the final insulation and the plasterboard but then the plasterboard wouldn't sit flush?

 

[sparkwright]

In the real world they would probably get clipped on the upper section of the rafters, and if any if any of the upper sections of the 100m insulation needs trimming to accomodate this then so be it, in the real world.

 

[mic2876uk]

In the real world they would probably get clipped on the upper section of the rafters, and if any if any of the upper sections of the 100m insulation needs trimming to accommodate this then so be it, in the real world.

So in the small uninsulated void above the first lot of insulation?

 

[skenk]

The zone regulation refers to 150mm from the top of the wall, not 150mm below the ceiling. Even if the vaulted ceiling was somehow considered a wall it would still be permitted by the 'corner' zone (150mm from an 'angle formed'). You would have to go up at the gables though, if the cables can't be run somehwere else.

 

[JohnW2]

The zone regulation refers to 150mm from the top of the wall, not 150mm below the ceiling. ...

It does, but if the 'top of the wall' is not the same as 'the bottom of the ceiling', what is it that is between the two?

...Even if the vaulted ceiling was somehow considered a wall it would still be permitted by the 'corner' zone (150mm from an 'angle formed').

I'm not so sure about that one. What the regulation actually says is "...within 150 mm of an angle formed by two adjoining walls or partitions." - so, unless you think that the ceiling qualifies as 'a partition' (it's certainly not a wall), then I don't think that it really applies in the case we're discussing.

However, regardless of the above, I agree with those who have said that if the cable is buried somewhere that one believes can reasonably be regarded as being in a 'safe' (aka dangerous!) zone, the that would certainly be good enough for me.

Kind Regards, John

 

[skenk]

It does, but if the 'top of the wall' is not the same as 'the bottom of the ceiling', what is it that is between the two?

Often cornice, sometimes over a foot high.

I'm not so sure about that one. What the regulation actually says is "...within 150 mm of an angle formed by two adjoining walls or partitions." - so, unless you think that the ceiling qualifies as 'a partition' (it's certainly not a wall), then I don't think that it really applies in the case we're discussing.

Like I said "EVEN IF IT WAS SOMEHOW CONSIDERED A WALL" but you do get buildings where the walls are also the ceiling - search "a frame buildings"

However, regardless of the above, I agree with those who have said that if the cable is buried somewhere that one believes can reasonably be regarded as being in a 'safe' (aka dangerous!) zone, the that would certainly be good enough for me.

Simply call them wiring zones instead of safe zones and you help to stop the spread of the wrong term

 

[JohnW2]

Like I said "EVEN IF IT WAS SOMEHOW CONSIDERED A WALL" but you do get buildings where the walls are also the ceiling - search "a frame buildings".

That's true, and it doesn't have to be an A-frame (or 'Chalet-style') building) - some of the rooms on the top floor of my house are like that. In that situation, in the absence of official definitions, it reduces to an essentially sematic question - personally, if there is no horizontal (or nearly horizontal!) part, I would probably think of it as 'wall all the way to the top, with no ceiling' at all - but views will undoubtedly vary. From the point-of-view of the 'safe' zones, it would seem very reasonably to regard it all as 'wall'.

Simply call them wiring zones instead of safe zones and you help to stop the spread of the wrong term

Agreed, since the term that is commonly used is obviously confusing/misleading. The problem, of course, is that the 'zone' means different things to different people. To the electrician, it indicates a place where it is allegedly 'safe' to install concealed cables, but to the person with a drill, nail or screw in their hand it represents a 'dangerous' place to penetrate a wall!

Kind Regards, John