J C Walker 1881-83, extended by James Shearer 1914-21; further extension by Stone Design Ltd of Stirling, 1990-93. 2 and 3-storey and basement rectangular-plan library comprising 2 adjoining rectangular-plan blocks. Original building Gothic Revival; extended in stripped Renaissance style to S/along St Margaret St; emphasis to corners of each block; bartizans and pavilion roof to original section; French pavilion roof and Dutch gable to NE corner of extension. Coursed stugged sandstone with polished sandstone ashlar dressings. Base course to principal elevations of both sections; moulded band courses between storeys to earlier section. Stopped roll-moulded surrounds to principal windows to earlier section (roll-mouldings to upper windows terminate at nook shafts with foliate capitals); moulded surrounds to principal windows to extension.
N (ABBOT ST) ELEVATION: asymmetrical composition. 3-storey entrance bay stepped forward as tower to left. Central entrance with shallow gabled porch with crocketted finial; gablehead inscribed 'THE GIFT OF ANDREW CARNEGIE ESQ TO HIS NATIVE CITY - THE MEMORIAL STONE WAS LAID BY THE DONOR'S MOTHER 27TH JULY 1881'. Moulded Gothic arch inscribed 'CARNEGIE PUBLIC LIBRARY' beneath hoodmould. Caernarvon-arched entrance set back with flanking nook-shafts of 2 orders with foliate capitals; tympanum carved with scene of rising sun and motto 'LET THERE BE LIGHT'; earlier 20th century 2-leaf glazed timber door. 2-light window above. Central 3rd floor window set beneath shouldered gable with carved panel and gableted pinnacle; decorative wrought iron finial. Flanking octagonal bartizans, each with single light window to 3 outer faces; shafts with foliate capitals in between; capitals linked by band course to central window. Carved and moulded bands to lower sections of bartizans; moulded cornices and conical roofs with wrought iron finials; linking machicolated band at lower level. 3 bays set back to right; 2 bays projecting to outer right; 2-light mullion window to each; bracketed eaves cornice. Pavilion roof above 2 outer right bays.
E ELEVATION: 3-storey single-bay elevation of original building to right. Pair of windows to ground floor; narrow basement window below to left. Single window above to right; small 2-light mullion window with long and short surrounds to outer left; panel carved with intertwining initials 'J C W' in between. 2-light mullion dormer window with shouldered gable and carved finial to 3rd floor. 3-storey tower-like stair bay of later section projects forward to left; chamfered at corners to upper stage with parapet-like eaves cornice surmounted by French pavilion roof. Pair of ground floor windows with roll-moulded surrounds. Breaking eaves centrepiece above comprising pair of vertically banded stair windows set back within pilastered surround surmounted by 5-tier Dutch gable. Right window stepped up at cill level; horizontal ashlar bands to right of bay at junction between 2 cills. Windows set back within segmental arches to either side of shared central pilaster; plinth-like panels at bottom of pilasters; flanking moulded outer bands surmounted by segmental-plan ledges supporting carved figures. Wide transom carved with heraldic insignia with flanking initials (respectively R R and M R) to centre of each window; narrower plain upper transom to left window. Projecting cills to both windows; decorative wrought iron balustrade to that to left. Gable inscribed '19-15' and 'A C' (intertwined) at base; flanking panelled obelisk pinnacles set at angle; both with wrought iron finials. Small architraved 1st floor window and piended dormer with overhanging eaves and swept sides to right return. 3 bays to left; 4-light mullion and transom window to ground floor and 2-light mullion window above to each. Polychromatic band courses link stair bay to lintels of windows to left. Inserted openings to basement (some blocked). Pair of plain horizontal panels above 1st floor windows. Obelisk pinnacle surmounted by carving of lion with shield to outer left of eaves.
S ELEVATION: later section adjoins 1990's extension to E. Blank elevation to W; harled above coursed rubble; ashlar base course. Stepped ashlar buttresses. Gable to left.
W ELEVATION: gable end of original section linked to No 5 Abbot St via late 20th century enclosed walkway. Later section to S harled over ashlar basement. Bands of windows linked horizontally at upper levels by band courses across cills and lintels; 2-light mullion windows to basement and 1st floor; 4-light mullion and transom windows to ground floor (one to 1st floor). Outer right bay stepped up slightly with pyramidal roof.
Mainly 3-pane timber sash and case windows to original section; single 2 and 3-pane metal frames with pivot sections to extension. Grey slate roofs where visible. Pair of gablehead stacks to S of extension (one harled) and one with projecting flue and moulded cornice to W of original section; narrow ridge stack (an addition) to E; round cans.
INTERIOR: glazed tunnel vault to part of extension. Half-turn main staircase to early 20th century extension with decorative wrought-iron baulstrade by Thomas Hadden (to architect's design). Timber panelling with carved decoration including Jacobethan mantelpiece to S of main staircase may have been moved from original section.