Long delayed DIY project coming up - planning to insulate loft at
ceiling level. But I've seen a couple of websites saying not to put
insulation over electricity cables, and I have several cables up there.
Is this really an issue?

Many thanks

On 07/09/14 14:07, JIP wrote:
Long delayed DIY project coming up - planning to insulate loft at
ceiling level. But I've seen a couple of websites saying not to put
insulation over electricity cables, and I have several cables up there.
Is this really an issue?

Many thanks

Only if you are running em flat out


--
Everything you read in newspapers is absolutely true, except for the
rare story of which you happen to have first-hand knowledge. €“ Erwin Knoll

On 07/09/14 14:59, The Natural Philosopher wrote:
On 07/09/14 14:07, JIP wrote:
Long delayed DIY project coming up - planning to insulate loft at
ceiling level. But I've seen a couple of websites saying not to put
insulation over electricity cables, and I have several cables up there.
Is this really an issue?

Many thanks

Only if you are running em flat out



And they are shower or cooker feeds. And all that means is some
calculation is necessary.

Lighting and 32A rings are generally OK unless a lot of things are
conspiring to work against you.

The other main issue is downlighters which will need hoods over them
otherwise they will overheat.

"Tim Watts" wrote in message
...
On 07/09/14 14:59, The Natural Philosopher wrote:
On 07/09/14 14:07, JIP wrote:
Long delayed DIY project coming up - planning to insulate loft at
ceiling level. But I've seen a couple of websites saying not to put
insulation over electricity cables, and I have several cables up there.
Is this really an issue?

Many thanks

Only if you are running em flat out



And they are shower or cooker feeds. And all that means is some
calculation is necessary.

The caculation is easy on these. Move the cables out of the insulation. They
will almost certainly be run at near to full load.

Lighting and 32A rings are generally OK unless a lot of things are
conspiring to work against you.

Adding insulation over a 2.5 T&E cable used on 32A ring would be wrong if it
the insulation makes it installation method 101 or 103

http://wiki.diyfaq.org.uk/index.php?...lation_Methods

The other main issue is downlighters which will need hoods over them
otherwise they will overheat.

The hoods are only needed for fire protection between floors when required
by part B of the building regs.

--
Adam

Tim Watts wrote:

On 07/09/14 14:59, The Natural Philosopher wrote:
On 07/09/14 14:07, JIP wrote:
Long delayed DIY project coming up - planning to insulate loft at
ceiling level. But I've seen a couple of websites saying not to
put insulation over electricity cables, and I have several cables
up there. Is this really an issue?

Many thanks

Only if you are running em flat out



And they are shower or cooker feeds. And all that means is some
calculation is necessary.

Lighting and 32A rings are generally OK unless a lot of things are
conspiring to work against you.

The other main issue is downlighters which will need hoods over them
otherwise they will overheat.

Well I have no idea what most of the cabling is - it was all done
before I bought the house. But the cooker and shower are at a far end,
so I doubt if they are involved. Most of it seems to be lighting, but
no downlighters involved.

Many thanks

--

On 07/09/14 18:14, ARW wrote:

The other main issue is downlighters which will need hoods over them
otherwise they will overheat.

The hoods are only needed for fire protection between floors when
required by part B of the building regs.

Correct me if I am wrong, but I thought it was considered necessary to
provide some space around a downlighter buried under insulation.

On 07 Sep 2014, "JIP" grunted:

Well I have no idea what most of the cabling is - it was all done
before I bought the house. But the cooker and shower are at a far end,
so I doubt if they are involved.

Those cable will be fatter than the others, as they are intended for higher
current. In the same way that ring main cable are fatter than lighting
cable.

--
David

On 07/09/14 18:14, ARW wrote:

Adding insulation over a 2.5 T&E cable used on 32A ring would be wrong
if it the insulation makes it installation method 101 or 103

http://wiki.diyfaq.org.uk/index.php?...lation_Methods

Yes - sorry - you are right. I was stuck on thinking 100mm insulation or
less for some reason which is OK. But not for 100mm

The other main issue is downlighters which will need hoods over them
otherwise they will overheat.

I cut 4" soil pipe to the length of the first layer of insulation (170mm
?) and cut holes so they poked through and were flush with the surface
of the insulation then just ran the top 100mm layer over the whole lot.

Much cheaper than the commercial alternatives.

On 07/09/14 21:56, "Pet @ www.gymratz.co.uk ;¬)" wrote:

The other main issue is downlighters which will need hoods over them
otherwise they will overheat.

I cut 4" soil pipe to the length of the first layer of insulation (170mm
?) and cut holes so they poked through and were flush with the surface
of the insulation then just ran the top 100mm layer over the whole lot.

Much cheaper than the commercial alternatives.




I've heard of clay flowerpots being used...

"Pet @ www.gymratz.co.uk ;¬)" wrote:

The other main issue is downlighters which will need hoods over them

I cut 4" soil pipe to the length of the first layer of insulation
Much cheaper than the commercial alternatives.

And much more flammable?

I'd not have said so myself. Most of the loft insulation here is over
cables. If a cable is getting even warm I'd imagine that would mean a
problem to start with.

Brian

--
From the Sofa of Brian Gaff Reply address is active
"JIP" wrote in message
o.uk...
Long delayed DIY project coming up - planning to insulate loft at
ceiling level. But I've seen a couple of websites saying not to put
insulation over electricity cables, and I have several cables up there.
Is this really an issue?

Many thanks

Interestingly, I noted a person was using pieces of pipe around downlighters
to act as heat loss areas in the insulation. However downlighters and power
transformers and psus are a whole other situation. I've often wondered
about the safety of such things if they get hot in use.
Brian

--
From the Sofa of Brian Gaff Reply address is active
"Tim Watts" wrote in message
...
On 07/09/14 14:59, The Natural Philosopher wrote:
On 07/09/14 14:07, JIP wrote:
Long delayed DIY project coming up - planning to insulate loft at
ceiling level. But I've seen a couple of websites saying not to put
insulation over electricity cables, and I have several cables up there.
Is this really an issue?

Many thanks

Only if you are running em flat out



And they are shower or cooker feeds. And all that means is some
calculation is necessary.

Lighting and 32A rings are generally OK unless a lot of things are
conspiring to work against you.

The other main issue is downlighters which will need hoods over them
otherwise they will overheat.

On 07/09/2014 22:04, Tim Watts wrote:


I've heard of clay flowerpots being used...

That was the other suggestion by our Electrician of the time.
Only ones I could find were a bit too shallow and they were also pretty
heavy so opted for his soil pipe suggestion.

JIP wrote:

Long delayed DIY project coming up - planning to insulate loft at
ceiling level. But I've seen a couple of websites saying not to put
insulation over electricity cables, and I have several cables up
there. Is this really an issue?

Many thanks

Thanks for all the replies

--

"Tim Watts" wrote in message
...
On 07/09/14 18:14, ARW wrote:

The other main issue is downlighters which will need hoods over them
otherwise they will overheat.

The hoods are only needed for fire protection between floors when
required by part B of the building regs.

Correct me if I am wrong, but I thought it was considered necessary to
provide some space around a downlighter buried under insulation.


But does a fire hood supply the required space?

--
Adam

On 08/09/14 19:58, ARW wrote:
"Tim Watts" wrote in message
...
On 07/09/14 18:14, ARW wrote:

The other main issue is downlighters which will need hoods over them
otherwise they will overheat.

The hoods are only needed for fire protection between floors when
required by part B of the building regs.

Correct me if I am wrong, but I thought it was considered necessary to
provide some space around a downlighter buried under insulation.


But does a fire hood supply the required space?


Honestly - not sure...

On Monday, September 8, 2014 6:36:11 PM UTC+1, JIP wrote:
JIP wrote:



Long delayed DIY project coming up - planning to insulate loft at

ceiling level. But I've seen a couple of websites saying not to put

insulation over electricity cables, and I have several cables up

there. Is this really an issue?



Many thanks



Thanks for all the replies



--

The 35W downlighters (12V) in our hall began giving trouble a wee while back. Investigation showed that my rather vague attempts at allowing a heat passage through the insulation some 20 years previously had not been that successful as not only had the holder contacts deteriorated but the choc block connectors looked somewhat melted too.

There's now 2 x 3W of LED in each position and the holders are barely warm - and the lighting is far better too !
Rob