You see some funny things when you visit a residential property which has been let for a number of years. In one such property recently, I came across an incoming water mains which had been repaired with PVC electrical insulation tape – but provided it complies with BS EN 60454-1:1995, which are the specifications for pressure-sensitive adhesive tape, then it’s fine.
Amazingly the damage to the flat itself was quite minimal but on the other side of the party wall, the wall was saturated. I can only assume the defective mains was repaired and the tape repair worked because the water was running in the flat. You come across very odd situations as a building surveyor.