Laying cable across loft insulation

[maharg]

Re-wiring a house at the moment and the loft insulation is 60 cm thick fibreglass laid on the original fibreglass insulation which turns into powder when touched.
Cant see the joists and the light and switch access holes are in the centre of the loft space.
Normally i would clip cable to joists but theinsulation is so thick all I really want to do is lay cable across it .
Is this acceptable.

 

[Darkwood]

It would be advisable to keep it off the insulation where possible so its not a trip hazard for the next loft visitor but with it been lighting and usually lightly loaded in comparrrison to the current carrying capacity of the cable running through insulation normally isnt an issue although still advise doing cable calcs to confirm.

 

[Des 56]

The trip hazzard can be assessed by each individual installation
A loft that is rarely used, it will pose no hazzard at all and laying it on the insulation is better for the cable ccc
If it is used for chucking a bit of christmas decorations up through the hatch then clipping around the trap would be in order
If it is well used then routing and clipping of the cable should be much improved
In the end until its function is changed it is no more than an unused void that does not require the cables to be secured

 

[Darkwood]

The trip hazzard can be assessed by each individual installation
A loft that is rarely used, it will pose no hazzard at all and laying it on the insulation is better for the cable ccc
If it is used for chucking a bit of christmas decorations up through the hatch then clipping around the trap would be in order
If it is well used then routing and clipping of the cable should be much improved
In the end until its function is changed it is no more than an unused void that does not require the cables to be secured

Only advising from experience we had an niceic inspection and was pulled on this point it dosnt matter if the loft isnt used for years or not its their for the duration of the installation and as i mentioned where possible keep it away but as we know it has to run through the insulation at some point and if the cable is stood on or kicked their is risk is of live wires been crushed or pulling out of fittings below, agreeable with all due respect this is a low risk and it is over the top but its good practice.

 

[Mac]

Standard electrical lighting cables can usually be placed within the insulation. This is generally done by tacking the cable to the side of the ceiling joist. Other cables and Heavy duty cables such as shower and cooker cables should be placed on top of the insulation to protect them from overheating.
Where recessed light fittings are used, the insulation around the fitting (for at least 80 – 100mm) should be removed allowing air to circulate and reduce heat build up.

 

[jellen]

as said above, the cables should be secured to the ceiling joists. The best method for doing this is to use the APPRENTICE