CT-03Check for cables, pipes, and work out the wall typeBefore drilling, find your stopcock (usually under the kitchen sink) and check it turns freely, so you can shut off the water fast if you hit a pipe. Run a cable and pipe detector over every mark, but don't trust it completely — detectors miss cables that run deep, sit in metal conduit, or are behind metal-backed plasterboard. If you have any doubt, isolate the relevant circuit at the consumer unit before drilling. On a stud wall, work out whether you have timber or metal studs: run a magnet or detector along the wall tracking the line of screw heads holding the plasterboard on, listen for the hollow sound between studs, and drill a small pilot hole at one mark — timber dust means a timber stud, fine grey metal swarf means a metal stud.