SR-02Find out what's behind the wall and stay safeBefore drilling anywhere, find your stopcock (usually under the kitchen sink) and check it turns, so you can shut off the water fast if you hit a pipe. Run a cable and pipe detector over the whole marked area, but don't trust it completely - it can miss cables that are deep, in metal conduit, or behind metal-backed board, and metal stud frames confuse cheap detectors further. If you're at all unsure, isolate the circuit at the consumer unit before drilling, and turn the water off at the stopcock before cutting into anything that could carry water. While you're at it, work out whether you have timber or metal studs: track a magnet or stud detector along the line of screw heads, listen for the hollow sound between fixing points, and check a small pilot hole - timber brings out pale wood dust, metal brings out fine grey swarf.