DCP-03Check what's behind the wall before you drillRun your detector over each bracket mark and a wide area around it — cables and pipes can run almost anywhere, not just in the zones you'd expect, and detectors miss cables that are deep, in metal conduit, or behind metal-backed plasterboard. Even if the detector shows nothing, drill carefully and be ready to stop. Find your stopcock now, usually under the kitchen sink, and check it turns freely, so you can shut the water off fast if you hit a pipe. If you have any doubt at all, isolate the relevant circuit at the consumer unit before you drill.