IB-03Check for cables and pipes before you drillCables and pipes can run almost anywhere in a wall, not just in the safe zones. Run your detector over the marked spots, but still treat the wall as if something is there — cheap detectors miss cables that are deep, in metal conduit, or behind metal-backed plasterboard. Find your stopcock first, usually under the kitchen sink, and check it turns. If you have any doubt at all, isolate the circuit at the consumer unit before you drill.