Installation Method

[Lusk]

What IM would you say for flat T&E laying on top of insulation and open to the air?  Cheers.

 

[Blue Duck]

102?

 

[Essex1]

103 IMO.  

 

[Doc Hudson]

102 and 103 are both described as "in a stud wall" see table 4A2 for reference, all of the 100, 102, 103, 104 refer to flat T&E buried in insulation. As this is not in insulation possibly none of these are relevant. However what is the potential of the cable being buried if further insulation is put in place?  The only Flat T&E method mentioning buried in insulation not touching any walls or joists is 103 as Essex suggested. What is the actual loading on this bit of cable in question, how critically close to its max capacity will it be running? If tolerance is not too much of an issue, pick a number or do heads or tails to decide.

Doc H.

 

[NozSpark]

I've seen something similar on the Voltilium site but in that case it was clipped to the joists..... they said it was ref method C

 

[steptoe]

I've seen something similar on the Voltilium site but in that case it was clipped to the joists..... they said it was ref method C

so did I,

I commented on it, but I'd hazard a guess they deleted it,  :slap

 

[NozSpark]

That's the reason I saw it.... :slap 

 

[Essex1]

Well it must be the case that securing cables to a thermally insulating material is not permitted. 

 

[Manator]

It is method C, there were some laboratory controlled tests carried out on cables in regards to the effects of thermal insulation which is why there are two methods referred to above. One method where the cable is fully enclosed by insulation and where one side of the cable is touching the wall for instance.

Heat will dissipate adequately enough if one surface is not enclosed by thermal insulation.

 

[SPECIAL LOCATION]

Surely its method  "D.I.Y"

or

method   "B.U.I.L.D.E.R"

or if none of the above got to be method "B.L.O.K.E.D.O.W.N.T.H.E.P.U.B"

:coat

who would ever leave cables lying on top of insulation anyway???

:C

 

[pewter]

The friday afternoon method

:innocent

 

[steptoe]

Surely its method  "D.I.Y"

or

method   "B.U.I.L.D.E.R"

or if none of the above got to be method "B.L.O.K.E.D.O.W.N.T.H.E.P.U.B"

:coat

who would ever leave cables lying on top of insulation anyway???

:C

Have you been hiding in my loft when I come home early,? :|

 

[Davethsparky]

Surely its method  "D.I.Y"

or

method   "B.U.I.L.D.E.R"

or if none of the above got to be method "B.L.O.K.E.D.O.W.N.T.H.E.P.U.B"

:coat

who would ever leave cables lying on top of insulation anyway???

:C

Id rather put them above it than below it or in it. 

 

[Rob_the_rich]

Surely its method  "D.I.Y"

or

method   "B.U.I.L.D.E.R"

or if none of the above got to be method "B.L.O.K.E.D.O.W.N.T.H.E.P.U.B"

:coat

who would ever leave cables lying on top of insulation anyway???

:C

loft insulation installers

better than covering them up surely?

 

[Essex1]

It is method C, there were some laboratory controlled tests carried out on cables in regards to the effects of thermal insulation which is why there are two methods referred to above. One method where the cable is fully enclosed by insulation and where one side of the cable is touching the wall for instance.

Heat will dissipate adequately enough if one surface is not enclosed by thermal insulation.

BS7671 specifically states 'not when secured to thermal insulation'. 

 

[SPECIAL LOCATION]

loft insulation installers

better than covering them up surely?

better clip them to a joist or flat to plasterboard surely.. 

e.g. 100 / 101

Prevents them been totally enclosed at a later date by captain loft insulator!

opcorn

 

[Essex1]

Id rather put them above it than below it or in it. 

Yes but clipped to a joist preferably. 

 

[Davethsparky]

Yes but clipped to a joist preferably. 

Yes but clipped to a joist preferably. 

Have you been in a modern new build loft? The insulation is always at least twice the height of the ceiling collars!

BS7671 specifically states 'not when secured to thermal insulation'. 

Wherabouts does it say that?

 

[SPECIAL LOCATION]

loft insulation installers

Actually most loft insulation installers I have seen the after effects of

Just bury everything under 200mm of insulation...

and most houses only just have enough slack in their loft wiring to get over the ceiling joists...

no way would they have 400mm to go up and back down again over fresh laid insulation.

opcorn  

 

[steptoe]

Surely no one in their right mind would be running the cables that close to their limit anyway,?

1.5 buried in 3' of insulation would still be good for 6amps driving 8lights,,,,

Ok, so maybe a shower circuit, but I think putting a 6mm on a 40amp is just cutting corners anyway, no matter how you look at it.