CS-03Check the fixing method if your wall turns out to be something elseIf it's actually solid brick or block, drill with a 6mm masonry bit to 50mm deep and use a red or brown wall plug with a 50-60mm screw. If it's plasterboard on timber studs, screw straight into the stud centre, or use a plasterboard toggle fixing rated for the weight between studs. If it's plasterboard on metal studs — common in flats and new builds — a pilot hole brings out fine steel swarf, not dust; use a self-drilling metal-stud fixing or toggle made for metal studs, never a plain wall plug or wood screw, which strips straight through 0.5mm steel. Metal studs alone won't hold heavy cube shelves properly, so fit a timber noggin between the studs first or fix through to the masonry behind. For dot-and-dab plasterboard over masonry, use a long fixing (60-75mm) that passes through the board's air gap and plugs into the solid wall behind.