Charles Rennie Mackintosh, (Honeyman and Keppie), E section, 1897. W section, 1907-9 (Honeyman, Keppie and Mackintosh). Art Nouveau. 2 storeys and basement; 4-storey return and S elevations. Polished ashlar, harled rear elevation, snecked rubble returns.
N ELEVATION TO RENFREW STREET: 8 bays, arranged 3-1-4 with single bay entrance at head of steps oversailing glazed basement area. Entrance with sculpted architrave, stylised cornice raised in centre with insignia; canted window to left with multiple geometric glazing bars. 1st floor balcony with wrought-iron balustrade, segmental headed pediment over 2-light window; canted window with independent eaves to left, narrow loop above recessed 2nd floor window with parapet in front; simple, raised polygonal turret to left. Outer bays: plain windows
double-height above ground, with glazing bars. Bold eaves cornice.
E ELEVATION TO DALHOUSIE STREET: shaped parapet wall to No 11; door with block lintel, fanlight above; central canted oriel projecting at 2nd and 3rd floor with varied windows in deep reveals; rising to corniced turret at
eaves. Plain basement and ground floor windows; bipartite window with segmental pediment above at 1st floor. 2 windows with linked, bowed cill at 2nd floor.
W ELEVATION TO SCOTT STREET: 6 bays. Polished ashlar basement and ground and upper floors in 3 W bays, otherwise snecked rubble. Wrought-iron grille to sub-basement. Shaped parapet wall to entrance with boldly
stepped architrave. Ground floor projecting stylised oriel windows with leaded lights. 3 S bays tall narrow leaded windows lighting library; canted, partially glazed sections above.
REAR ELEVATION SW RETURN: partly recessed leaded windows to ground floor, ashlar dressed central section above, centrally glazed overhanging, corbelled corridor. Boundary wall with piers, wrought-iron railings.
INTERIOR: Original Glasgow School detailing throughout. Library to W with original fittings and furniture.