Cavity Wall Insulation with Cables

G

gjones

Guest
What Cavity Wall Insulation products can you use if you have a number of existing cables runnning inside your cavity wall? It appears that products such as polyethelyene beads and (some) rockwool are unsuitable?
 
You may have to sheath the cables if they are not already in metal conduit or proprietary plastic tubing.

I was astonished to learn that two supposedly inert hydrocarbon materials like closed cell thermal insulation board and wiring electrical insulation could react.
Yet I have seen proof of it from an electrician on a job I took to site, when I questioned whether it was just for good husbanding of cable runs or was there another reason.

He showed me a piece of cable he took everywhere with him, which had non-melted beads off the wall insulation apparently "eating" into the wiring insulation, stuck to it and eroding it.
Wiring should be protected generally as it helps prevent short circuit from rough handling close to them (drilling and fixing items to walls and ceilings) and rodent attack.

Running cables inside your cavity wall is something I haven't come across before and isn't something I would normally countenance.
Insulation is placed within a cavity partly to protect it from damage and fire risk - what happens if there's a short?

Mind you if it was intended not to insulated it in the first place, that could have been an exception to the rule.
However for ease of fixing, repair, extending the circuits and connecting, internal routing is the norm.

ONQ.

[broken link removed]

All advice on AAM is remote from the situation and cannot be relied upon as a defence or support - in and of itself - should legal action be taken.
Competent legal and building professionals should be asked to advise in Real Life with rights to inspect and issue reports on the matters at hand.
 
According to IAB, Cosytherm White Wool and Knauf Supafil are products that appear to be okay to use with cables? Has anybody experience of using either?

You are right when you say the cables should be re-routed or sleeved but this could prove to be very expensive if a number of cables are run through the cavity over the years due to various renovations - this is a short cut that a few builders have told me they have used over the years.
 
I wouldn't accept that workmanship, notwithstanding the compatibility of the insulation.

Electrical cables not properly protected in what is an uninsulated damp environment is just asking for moisture to build up in the cable.

ONQ.

[broken link removed]

All advice on AAM is remote from the situation and cannot be relied upon as a defence or support - in and of itself - should legal action be taken.
Competent legal and building professionals should be asked to advise in Real Life with rights to inspect and issue reports on the matters at hand.
 
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