One variation of a panelized structural building system includes, a set of wall panels, each including: an outer face; a set of hardpoints, each arranged proximal a corner of the outer face, defining a lateral wall panel datum facing outwardly from a side of the wall panel, and defining an exterior façade mount facing outwardly from the outer face; and a load-bearing structure extending between the set of hardpoints and inset from a maximal wall panel perimeter defined by the set of hardpoints; wherein the set of wall panels are assemblable into a wall with lateral wall panel datums—defined by hardpoints in adjacent wall panels—abutting to laterally space the set of wall panels along the wall. The system also includes a set of exterior façade panels configured to install onto exterior façade mounts—defined hardpoints in adjacent wall panels—to conceal outer faces of these wall panels.