A plank (10) for a fagade system comprises a facia (12), a joining lip (20), and a hook (30). The joining lip (20) is recessed behind and extends alongside the facia (12) to overlap with an adjacent plank. The hook 30 extends behind the facia to engage a wall-mounted retainer (38, FIG. 3D). The plank 10 comprises a rail 26 to conceal the hook (30). In one aspect, the rail 26 extends beyond the hook to abut the wall, to restrict a tilt of the plank. In one aspect, the joining lip 20 comprises alignment features (22) for positioning another retainer (40, FIG. 3D). In one aspect, the facia (12) comprises blind grooves (52, FIG. 8B) mimicking inter-plank interstitial grooves. The aspects individually and combined reduce the resources required for covering a large wall area with aligned cladding facias.