AB-02Work out what's really behind the plasterLath and plaster is just the finish — it sits over timber studwork, or over timber battens fixed to solid brick or block. Tap the wall: solid masonry sounds dull throughout, a stud wall sounds hollow between studs and firmer over each one. Run a detector or a strong magnet across the wall at drilling height — regular points roughly 400-600mm apart are the nail heads holding the lath to studs. Lath and plaster is never fixed to modern metal studs, so if a detector picks up metal framework, you actually have plasterboard, not lath and plaster — different fixings apply. If still unsure, drill one small 3mm test hole: timber dust means a stud, crumbly grey dust means only plaster and lath with nothing solid behind.