Following the recent thread about cables passing through insulation it has left me with a dilemma regards the supply cable.

My supply cable emerges out of the sub-floor and passes through an approx. 50mm gap between the first joist and the wall. However the run of the cable is not vertical due to the alignment between the entry point and the cutout the alignment is approx. 150 - 200mm out and the result is that the cable forms a lazy S in the space between joist and wall. This makes sleeving impossible.

Originally, I was simply going to PU foam the gap but the previous thread has made me a bit cautious. I could possibly get some of that flexible corrugated sleeving and split it along its length to get it around the cable but suspect there would be gaps at the bends allowing PU in against the cable. To my mind the gap in insulation is too great to ignore so I would welcome any advice please.

Richard

On Monday, 12 October 2020 09:51:58 UTC+1, Tricky Dicky wrote:
My supply cable emerges out of the sub-floor and passes through an
approx. 50mm gap between the first joist and the wall. However the
run of the cable is not vertical due to the alignment between the
entry point and the cutout the alignment is approx. 150 - 200mm out
and the result is that the cable forms a lazy S in the space between
joist and wall. This makes sleeving impossible.

Move the cutout? :-)

Just squirty foam it and say it was like that when you moved in.

Owain

On 12 Oct 2020 at 09:51:55 BST, "Tricky Dicky" wrote:

Following the recent thread about cables passing through insulation it has
left me with a dilemma regards the supply cable.

My supply cable emerges out of the sub-floor and passes through an approx.
50mm gap between the first joist and the wall. However the run of the cable
is not vertical due to the alignment between the entry point and the cutout
the alignment is approx. 150 - 200mm out and the result is that the cable
forms a lazy S in the space between joist and wall. This makes sleeving
impossible.

Originally, I was simply going to PU foam the gap but the previous thread has
made me a bit cautious. I could possibly get some of that flexible corrugated
sleeving and split it along its length to get it around the cable but suspect
there would be gaps at the bends allowing PU in against the cable. To my mind
the gap in insulation is too great to ignore so I would welcome any advice
please.

Richard

Are you worried about insulation derating the cable or chemical effects on the
cable jacket? I must admit I would assume in both cases it is designed to go
in some unpredictable unsavoury places and would be ok. But I have no basis
for saying that.


--
Roger Hayter

On Monday, 12 October 2020 at 11:08:01 UTC+1, Roger Hayter wrote:
On 12 Oct 2020 at 09:51:55 BST, "Tricky Dicky" wrote:

Are you worried about insulation derating the cable or chemical effects on the
cable jacket? I must admit I would assume in both cases it is designed to go
in some unpredictable unsavoury places and would be ok. But I have no basis
for saying that.


--
Roger Hayter

Roger it is about derating the cable, I know the PU should not react with the cable. Previously it was buried maybe not intentionally in a thick lump of plaster which fell away when I pulled the old floorboards out and was finally able to see the situation.

Owain, I take it from the smiley moving the cutout was not a serious suggestion, apart from involving the DNO again there is nowhere for it to go things are very tight around that area with the CU and meters.

Richard

On 12/10/2020 09:51, Tricky Dicky wrote:
Following the recent thread about cables passing through insulation
it has left me with a dilemma regards the supply cable.

My supply cable emerges out of the sub-floor and passes through an
approx. 50mm gap between the first joist and the wall. However the
run of the cable is not vertical due to the alignment between the
entry point and the cutout the alignment is approx. 150 - 200mm out
and the result is that the cable forms a lazy S in the space between
joist and wall. This makes sleeving impossible.

Originally, I was simply going to PU foam the gap but the previous
thread has made me a bit cautious. I could possibly get some of that
flexible corrugated sleeving and split it along its length to get it
around the cable but suspect there would be gaps at the bends
allowing PU in against the cable. To my mind the gap in insulation is
too great to ignore so I would welcome any advice please.

Richard

foam doesn't affect the wiring chemically but the insulation may cause
overheating in some home wiring cases. I doubt this is relevant for a
short run of armoured or 100A tails.

--
"Nature does not give up the winter because people dislike the cold."

ۥ Confucius

On 12/10/2020 11:23, Tricky Dicky wrote:
On Monday, 12 October 2020 at 11:08:01 UTC+1, Roger Hayter wrote:
On 12 Oct 2020 at 09:51:55 BST, "Tricky Dicky"
wrote:

Are you worried about insulation derating the cable or chemical
effects on the cable jacket? I must admit I would assume in both
cases it is designed to go in some unpredictable unsavoury places
and would be ok. But I have no basis for saying that.


-- Roger Hayter

Roger it is about derating the cable, I know the PU should not react
with the cable. Previously it was buried maybe not intentionally in a
thick lump of plaster which fell away when I pulled the old
floorboards out and was finally able to see the situation.

Owain, I take it from the smiley moving the cutout was not a serious
suggestion, apart from involving the DNO again there is nowhere for
it to go things are very tight around that area with the CU and
meters.

Richard

A foot of foam on a meter of fat copper cable is not going to derate
anything significantly.

Copper conducts heat damned well

I am fairly sure my armoured incoming comes up a foam filled pipe...

--
To ban Christmas, simply give turkeys the vote.

On 12/10/2020 10:45, wrote:
On Monday, 12 October 2020 09:51:58 UTC+1, Tricky Dicky wrote:
My supply cable emerges out of the sub-floor and passes through an
approx. 50mm gap between the first joist and the wall. However the
run of the cable is not vertical due to the alignment between the
entry point and the cutout the alignment is approx. 150 - 200mm out
and the result is that the cable forms a lazy S in the space between
joist and wall. This makes sleeving impossible.

Move the cutout? :-)

Just squirty foam it and say it was like that when you moved in.

Owain


Unless you are trying to exclude creepy crawly's or stop a nasty
cold draught, just ignore it.

On Mon, 12 Oct 2020 02:45:34 -0700 (PDT),
wrote:

My supply cable emerges out of the sub-floor and passes through an

approx. 50mm gap between the first joist and the wall. However the

run of the cable is not vertical due to the alignment between the
entry point and the cutout the alignment is approx. 150 - 200mm
out
and the result is that the cable forms a lazy S in the space
between
joist and wall. This makes sleeving impossible.

Fix some bits of wood to joist projecting to wall either side of the
incommer to form a box for it. Squirty foam outside of the box,
lightly stuff box with fibre glass insulation and ali tape over.

Presumably you're insulating under the floor, 50mm is wide enough for
celotetx to be installed. I'd avoid glueing the joist to wall with
squirty foam, even if the wall is dry. Some squirty foams are
porous...

Just squirty foam it and say it was like that when you moved in.

Hum, even with the remote chance that the foam will damage the cable
the though of a short on the incomer before the cutout doesn't sound
like a good idea.

--
Cheers
Dave.

On Monday, 12 October 2020 11:23:26 UTC+1, Tricky Dicky wrote:
things are very tight around that area with the CU and meters.

You can move them too :-)

Owain

I'd seriously doubt foam there on a short run of cable would make any
difference at all, indeed because its quite easy to dig out one would not
really have aan issue to get at the cable.
Brian

--
--
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
wrote in message
...
On Monday, 12 October 2020 09:51:58 UTC+1, Tricky Dicky wrote:
My supply cable emerges out of the sub-floor and passes through an
approx. 50mm gap between the first joist and the wall. However the
run of the cable is not vertical due to the alignment between the
entry point and the cutout the alignment is approx. 150 - 200mm out
and the result is that the cable forms a lazy S in the space between
joist and wall. This makes sleeving impossible.

Move the cutout? :-)

Just squirty foam it and say it was like that when you moved in.

Owain

On Tuesday, 13 October 2020 at 07:56:31 UTC+1, Brian Gaff (Sofa) wrote:
I'd seriously doubt foam there on a short run of cable would make any
difference at all, indeed because its quite easy to dig out one would not
really have aan issue to get at the cable.
Brian

--
--
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
wrote in message
...
On Monday, 12 October 2020 09:51:58 UTC+1, Tricky Dicky wrote:
My supply cable emerges out of the sub-floor and passes through an
approx. 50mm gap between the first joist and the wall. However the
run of the cable is not vertical due to the alignment between the
entry point and the cutout the alignment is approx. 150 - 200mm out
and the result is that the cable forms a lazy S in the space between
joist and wall. This makes sleeving impossible.

Move the cutout? :-)

Just squirty foam it and say it was like that when you moved in.

Owain

The latest, straight from the horses mouth, I got in touch with the DNO and their advice is not to use PU foam around the supply cable. So I will stuff the gap with some Rockwool on one side and I can get a bit of wood down the other side so I can fill that with PU and then a bit of judicious use of sealing tape should leave it insulated as best can and as air tight as possible. Thanks for all the suggestions.

Richard

On Tuesday, 13 October 2020 15:52:03 UTC+1, Tricky Dicky wrote:
The latest, straight from the horses mouth, I got in touch with the
DNO and their advice is not to use PU foam around the supply cable.

ooops.

Owain