In article ,
N. Thornton wrote:
Polystyrene foam and PVC cable are a known problem. I gather the
polystyrene slowly turns the PVC to goo somehow, and the result is
eventual fire.

I discovered some cable laid across poly sheet long after some building
work at home. The cable had sunk through the poly and was resting on the
plasterboard ceiling. But in other ways was still intact - although the
PVC *may* have been slightly brittle. But in no way a fire risk unless
moved.

--
*I don't suffer from insanity; I enjoy every minute of it.

Dave Plowman London SW 12
RIP Acorn