WR-02Work out what's behind the wallIf the rail sockets fix into the wardrobe side panels, you're drilling into board or timber, not the wall. If they fix into the actual wall (common in alcove wardrobes), use a stud detector to check for a timber or metal stud pattern, or run a magnet along the wall to find screw heads holding plasterboard to a metal frame. A dull thud when you knock is solid masonry or dot-and-dab; a hollow sound is a stud wall or lath and plaster.