Sydney Mitchell based on sketch designs by Dr Clouston the physician superintendent, designed 1887, begun 1889, E half of main building; hospital and 3 villas built by 1894, all in a Free Renaissance style of mixed Francois Premier to Henri Quatre inspiration showing also the influence of the Nesfield-Champneys and Anderson & Browne manners. The
buildings are of red coursers with biscuit coloured dressings and small-paned windows and are roofed in green slates throughout.
Spectacular towered and gabled picturesque composition approx. 375' long on steeply sloping site, complex E-plan (courtyards open to S) with N projection forming NE entrance forecourt. Comprises 2 approximately symmetrical blocks of irregular L-plan and mainly 3-storey with dormerheads, basements and oblong towers with timber cupolas rising a storey higher in angles, housing wards, bedrooms, and public rooms, stepped in slope on either side of high 6-bay central N-S. hall block with flanking staircases, that on the W carried up as massive square 8-storey 32' square tower 100' high with corbelled angle turret top 4 at NE, 3-bay arcaded top stage and platformed roof with balustraded parapet; 2-storey drawing and billiard room projecting from hall block centre of S front, 2-storey and basements wing centre of N front with pyramid roofed engineers pavilion at N end of composition beyond driveway; porch in NE re-entrant angle diagonally set, Roman Doric pilastered with distyle in antis treatment on flank. Rich and varied detail of great refinement, ogee-roofed circular towers of Francois Ier derivation with pilastered windows at N angles of ward blocks (2 on NW, 1 at NE) with fluted pilastered friezes, another 2 at angles of S wing all with bell-roofs carried up into timber cupolas at the latter; some roofs French pavilioned, some have rich and varied shaped gable treatment, those at hall block and at S wing with armorial panels several having shell-headed niches: tall French chimney stacks with semi-circular divisions between flues instead of pots.
Outstanding interior work, notably at grand staircase leading to central pilastered 6-bay great hall 63' x 33' x 45' high lit by clerestory windows in arched ceiling and large Venetian in N gable, chimneypieces in recesses, balcony for musicians, panelled in oak to a height of 12', rich original decorative wall treatment largely survives.
Main block 2-storey and attic with pavilion roof and tall stacks, main frontage to N has off-centre semi-circular pedimented section 3-windows wide with the windows linked by ashlar apron panels 3-window to left with pediments at ground floor, single pedimented ground floor window to right and octagonal NW corner bay with spired roof. Long low single-storey wing to E with piended roofs and ogee roofed timber cupolas, turret in stepped NE angle, canted bay features on S. Sited on axis of main building and effectively extending its composition uphill on the W although separated by two driveways.
Cottage hospital type, E part single-storey and mansard attic, E front 2-window and centre door with pedimented stone dormers centred on the windows below; W wing low without attic; sun-lounge on S front somewhat altered.
2-storey with dormerheads, basement and attic in high French pavilion roof, effectively sited on high rising ground. Symmetrical E front with pedimented tripartite doorpiece approached by branched perron with elaborate wrot-iron work pedimented dormer-head window, above framed in 2 tall stacks adjoining octagonal corner bays with spired roofs; flanks and rear asymmetrical, further octagonal corner tower at SW.
South Craig Villa;
2-3 storey in fall of ground effectively sited on high ground with balustraded terrace on high retaining wall along greater part of E flank. Entrance in pedimented doorpiece approached by stair with wrot-iron work, semi-circular stair turret projects from centre of flank immediately to N; SW projection ends in 2-octagonal-corner bays, N gable recessed at NE corner and filled out by lower flat roofed section, tall canted bay to W; canted bay S end of W flank.
Lodge: single-storey and attic, bargeboarded gable front with single-storey canted bay and slope of main roof extended over semi-elliptically arched footgate, shaped gable with rolled skewputts to drive. Gatepiers banded, flambeaux finials with acanthus bases, wrot-iron railings and gates.