AB-05Mark, drill and fix according to your ceiling typeTimber joist: drill a 3mm pilot hole in the centre of the joist and drive a 6mm x 100mm coach screw or the bolt supplied, never rely on the plasterboard alone. Metal joist, common in flats and newer steel-frame garages: a plastic plug or ordinary wood screw strips straight through 0.5-1.2mm steel, so use a self-drilling metal-stud screw for light brackets only, and never hang the full loaded rack from metal joists alone - fit a timber noggin cut to span between two joists, screw it to both, then fix the rack to the noggin. Lath and plaster ceiling: find the real joist as above, then drill through the plaster and lath into solid timber and use a coach screw that bites at least 40mm into the joist, with a helper supporting the ceiling from below as old plaster keys can crack and drop. Solid concrete or masonry soffit, common where the garage sits under another room: drill with an SDS drill and masonry bit to the plug maker's stated depth, usually 50-60mm, then fit a heavy-duty masonry plug and screw sized for your load, undersized fixings here pull straight out. Dot-and-dab doesn't apply to a ceiling, it's a wall-lining method, so ignore it even if your garage walls are finished that way.