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Whilist investigating leaking pipes on my flat roof I noticed some dodgy looking wiring. I have electric cable exiting my bathroom external wall and routed along the outside wall and into a homebuilt conservatory. The cable is the thick grey cable used under floorboards. I belive it must run underneath the floorboards beneath the bath also. The elecrical work was completed by the last owners - so far every job I tackle unearths DIY hell. Can someone please advise if the cable route is safe, I'm concerned about water from the bath and UV damage to unprotected cable outside.
Thanks, Neilos

Although UV can damage twin and earth cable I have seen it used outside many times and other then slight colour change to outer sheave I have not seen any problems due to UV. However it would depend on how run and if it was in a sun trap there could be a problem but unlikely.

The cable is normally water proof and only the ends of the cable need protecting from water ingress.

I would not use twin and earth to power a submersible pump but it would not have a problem with splashes.

Having said that it is clearly not the correct cable for outside and nearly all cable designed for outside is black. (For UV) But it is mechanical strength that is mainly considered rather than electrical insulation strength. So if the route is so that it is unlikely to be damaged then not really something which needs urgent attention.

However the IET/BSI who issue the wiring regulations recommend all wiring is periodically inspected and for domestic the period is longer than commercial and set at 10 years or change of occupier which ever is the sooner. So on moving into the house an inspection should have been completed. With owner occupier it is a recommendation but with any rented accommodation then it is very much enforced although not sure if legal or an insurance requirement. I would suggest to read the report and see what it has highlighted. And if not done then I would consider getting it done.

Thanks Eric for taking the time to write such a good response.
Neilos