SH-04Check for cables and pipes, and know your isolation pointsCables and pipes can run almost anywhere, including up through stud walls into sloped ceilings, so use a cable and pipe detector along your marked line before drilling. Detectors can miss cables that are deep, in metal conduit, behind metal-backed plasterboard, or running outside the usual safe zones — and a metal stud frame can confuse cheap detectors further, so still treat every hole as if something could be there. Find your stopcock now, usually under the kitchen sink, and check it turns freely. If you have any doubt at all, isolate the relevant circuit at the consumer unit before drilling, and turn off the water at the stopcock before cutting into anything that could carry water.
RULESKNOW THE RULES
There's no specific regulation covering shelf fixing, but Part P of the Building Regulations covers electrical safety — if you damage a cable, get it checked or repaired by a competent person, not just taped over.