twin and earth cabling size for commercial buildings

[davesparks]

Being commercial, will it be open to public? If it is then isn't thr consensus to use FP or similar?

Not quite, I think you may be thinking of LSF/LSOH type cables. LSF T&E exists.

 

[davesparks]

Clipped in a cavity, doesn't sound right. Think the installation method needs looking at a bit more closely.

Why not? What's wrong with cables being clipped in a cavity?

 

[Electro-tech]

Why not? What's wrong with cables being clipped in a cavity?

Depends on the purpose of the cavity & what else will end up in there, other than a cable route. Especially an external cavity wall.

 

[nicebutdim]

Depends on the purpose of the cavity & what else will end up in there, other than a cable route. Especially an external cavity wall.

To be fair to the OP, their comments indicate partition walls and not external cavities in which it would be nigh on impossible to clip cables.

 

[default]

To be fair to the OP, their comments indicate partition walls and not external cavities in which it would be nigh on impossible to clip cables.

Can it still be classed as clip direct. Maybe reference method G?. And if they're stud walls off the outer block work there's Surely going to be insulation.

 

[nicebutdim]

Can it still be classed as clip direct. Maybe reference method G?. And if they're stud walls off the outer block work there's Surely going to be insulation.

OP stated internal walls with no thermal insulation.

 

[default]

OP stated internal walls with no thermal insulation.

Still can't be classed as clipped direct. It's in a wall.

 

[cireland]

There is no exact reference method for this but I'd say clipped direct is closest.

 

[default]

Still can't be classed as clipped direct. It's in a wall.

And

There is no exact reference method for this but I'd say clipped direct is closest.

I'd say 103. If there's an EICR done in the future they either won't have the original test to go by or they'll look at it and think who ever tested it put down the wrong classification. I do sometimes think the installation references could do with one or two more. C'est La Vie

 

[cireland]

103 is with thermal insulation which greatly de-rates the cable.

 

[default]

103 is with thermal insulation which greatly de-rates the cable.

Depending on length of run. Anyway this is all hearsay. That's why you would need more info. If someone said to design an installation & the installation method was " Behind the wall in the cavity " you'd want a bit more to go on. "Throw me a fricking bone". Clipped direct it is not.

 

[cireland]

It is still the closest to the actual installation. There is no insulation which rules out the 100's.
There is no tray, conduit or trunking. It sure as hell ain't method G.
The only difference between this and 'C' is there are no clips.

 

[default]

It is still the closest to the actual installation. There is no insulation which rules out the 100's.
There is no tray, conduit or trunking. It sure as hell ain't method G.
The only difference between this and 'C' is there are no clips.

And the fact it says clipped direct. I though that ment on the surface & visible, which it wouldn't be. Form what the OP is suggesting there is no classification. This is a new install with new walls going up. It's been surmised it's somehow behind an internal wall, in a cavity, clipped, with no insulation present. All I'm saying is more classification is required. You can't price for a job with best case scenario. It's worst case or having the correct information.

 

[JBW175]

Well he’s going have to clip it to something, or put it in containment of some sort.

We can’t have cables just hanging round unsupported throughout their runs.

 

[default]

Well he’s going have to clip it to something, or put it in containment of some sort.

We can’t have cables just hanging round unsupported throughout their runs.

Who said you could, that's why you'd go back to the main contractor for more information, and if it went in some sort of containment that would also change the outlook.