Reference method / routing guidance for cable on a wall with 25mm Celotex

PAUL BERRY · May 30, 2019

I wonder if anyone could assist with this query please ? I am a newbie, so any guidance or alternatives would be greatly appreciated.

I need to run a ring final partly against a wall with internal 25mm Celotex type insulation. The additional Celotex being needed due to reduced cavity insulation. Diagram below ! Also fyi, the Celotex and board are separate, not ‘backed’.

I’m trying to decide whether to “1”- clip to the thermal block, flush (with capping), under the Celotex; or “2”-go between Celotex and board, and consider the respective pro’s and con’s of each. …or any other options ?

I’m not 100% sure from the BBB what the reference method would be for the first route. Possibly 103 ? which would affect my ccc somewhat.

Taking route 2 would (might?) need me to channel slightly into the Celotex which is also frowned upon. ….What would you do ?

[ElectriciansForums.net] Reference method / routing guidance for cable on a wall with 25mm Celotex

Charlie_ · May 30, 2019

Cap cables straight onto block work and into back boxes

Ian1981 · May 30, 2019

If the cables are clipped to the thermalite block work then it is more like reference method C , as one side of the cable can loose its heat through the block work and into the cavity of the wall , the cable is not touching one side of the plasterboard in a cavity wall nor is it completely surrounded by insulation in a cavity wall.

Appendix 4 might give a different reference method so it’s worth having a look at it.

Wilko · May 30, 2019

As per @Charlie_ and @Ian1981, I also prefer route 1 against the block work. IMHO this looks most like method 102, which is suficientemente bueno. I think route 2 looks most like method 3, which is no está bien

.

PAUL BERRY · May 30, 2019

Charlie_ said:
Cap cables straight onto block work and into back boxes

Cheers Charlie

PAUL BERRY · May 30, 2019

Ian1981 said:
If the cables are clipped to the thermalite block work then it is more like reference method C , as one side of the cable can loose its heat through the block work and into the cavity of the wall , the cable is not touching one side of the plasterboard in a cavity wall nor is it completely surrounded by insulation in a cavity wall.

Appendix 4 might give a different reference method so it’s worth having a look at it.

Thanks Ian, I'll have another check over App 4 too

PAUL BERRY · May 30, 2019

Wilko said:
As per @Charlie_ and @Ian1981, I also prefer route 1 against the block work. IMHO this looks most like method 102, which is suficientemente bueno. I think route 2 looks most like method 3, which is no está bien .

Cheers Wilko, and thanks for the Spanish lesson too. I rarely get beyond "dos cervezas por favor"