Early 19th century; expanded by George Matheson, post 1850; greatly enlarged and remodelled by Arthur Sydney Mitchell, 1885 - 1887; incorporating since circa 1990 classical archway, dated 1684, moved from Dunbar. Substantial enlargement and reworking in Scottish Arts and Crafts, 17th century manner of shooting lodge from existing 2-storey, rectangular grieve's house forming now 2-storey and attic, rambling-plan country house. Red sandstone rubble with red sandstone ashlar dressings and yellow painted harl. Base courses to canted windows, each with jettied principal floors with cill courses and roll-moulded arrises. Chamfered arrises to remaining windows.
S (PRINCIPAL) ELEVATION: advanced outer gables each with 2-storey canted window and small gablehead window above. Recessed centre bays with single storey entrance porch in re-entrant angle to left (window to S and door on right return) and exposed rubble stair tower in re-entrant angle to right with narrow windows, corbelled parapet and pedimented attic dormerhead breaking into conical roof; loggia formed at centre by 1st floor conservatory spanned between outer bays, given centrepiece below of open pedimented timber archway on paired Jacobean columns, with irregular ground floor windows behind; 1st floor conservatory with border-glazed base course, small-pane lights and raised ridge ventilating panes crowned by ornate iron brattishing. 2 segmental-pedimented dormer headed windows behind and lop-sided gabled stone wallhead dormer in re-entrant angle to left.
E ELEVATION: courtyard, closed by screen walls and Lochend arch (see below) to right. Return of elevation with advanced, 3-storey chimney-headed gable off-centre left with small ground floor window, paired windows to principal floor, gablehead with blank square ashlar panel with segmental pediment. Flanking bay to outer left with oculus at ground and window by re-entrant angle at 1st floor; flanking bays to right with 1st floor window as above and further smaller window above lean-to coal bunker projection, and below harled wallhead dormer with curvilinear head.
W ELEVATION: 2 irregular gabled bays at centre, that to left recessed with tall stair windows, that to right with 2-storey canted windows to left and small window at ground floor right and in gablehead; balcony above stone projection in re-entrant angle to right with decorative timber balustrade and lean-to tiled roof, door and window behind, previously with forestair, removed on restoration circa 1990; small window to right and 1st floor window to outer right beyond substantial, shouldered wallhead stack; 2 bays to outer left with irregular windows, breaking eaves in stone wallhead dormer with segmental-pedimented dormerhead to left of advance bay. Recessed to outer left, original lower 2-storey, 3-bay slate-roofed grieve's house: projecting central bay with central window, corbelled half-timbered 1st floor with bipartite window; to outer bays, mismatched windows. To left return, see STABLES AND HAYLOFT. To right return, adjoining later house.
COURTYARD ELEVATION: principal range with lopsided gable to outer left of courtyard elevation and irregular windows, including 2 pedimented dormers breaking eaves. Link block with original house in re-entrant angle with W wing, with 1st floor orielled rectangular window to left and oculus to right; ashlar birdcage bellcote with ogival cap to gablehead at right angles behind. Piend-roofed grieve's house with gabled, harled porch projection, to right.
STABLES AND HAYLOFT: L-plan range closing courtyard at NE corner. N-S arm dominated by leaded ventilator with ogival cap and weathervane finial; large later window in S gable with oculus above, stable windows to E with gabled hayloft dormer above, and further window to outer right. Catslide lean-to in re-entrant angle to courtyard. Gig-house/carport formed between projecting gables to N with glazed canopy.
LOCHEND ARCH: 1684 (see NOTES), cream sandstone ashlar classical arch after Serlio comprised of keystoned semi-circular arch flanked by small niches masked by pedestalled Doric columns supporting advanced pediment with full entablature and dated cartouche in tympanum; bold foliate carving to spandrels and fluted, pedestalled pilasters flanking. Low harled screen walls (circa 1992) abutting and closing court.
Small-paned glazing predominantly in sash and case windows, some casements to smaller and lesser windows, some fixed pane. Red tiled roofs, except original building with swept eaves and grey slates. Red sandstone crowsteps and margined wallhead stacks with moulded coping. Swept roof bipartite and single windowed dormers.
INTERIOR: sumptuous Arts and Crafts and Scottish 17th century interior, almost entirely Sydney Mitchell, 1885-7. Several Dutch timber classical chimneypieces. Doors with distinctive panel arrangement. Panelled ingoes. Arches to window openings and to corridors with panelled soffits. Entrance hall with wainscot panelling with moulded frieze, 17th century carved baluster crowned piers bearing landing balcony above with arcaded, fine barley sugar balustrade; carved, canopied red sandstone ashlar chimneypiece with black marble Ionic columns supporting consoles. Stairwell with ornate timber barley sugar balustrade, Jacobean finialled newel posts and panelled walls. Billiard Room with panelled dado, ingleneuk in segmentally arched recess with marble chimneypiece flanked by small windows, arcaded plasterwork frieze and barrel-vaulted roof with plasterwork robs; canted window recess; Alastair MacLeod mural paintings of mythological and esoteric subjects, circa 1990. Drawing room with built in cupboards, part-glazed with canopied recess at centre. Decorative encaustic tiles to conservatory and decorative cast-iron staging.
POWER HOUSE: small, single storey gabled building to NE of house, crowstepped in en suite materials, door to S gable, 2 windows breaking eaves to E with swept dormerheads. Remains of sawmill machinery lying nearby.
BRIDGE: mid 19th century. Stone rubble, 2-arch bridge to S of house over Leithen Water with small cutwater buttresses to centre pier, voussoirs and course of vertical masonry below upper coping. Apparently housing pipes carrying water to Leithen Lodge from reservoir to S.
SUNDIAL: probably late 17th / early 18th century. Lectern-shaped sundial on later ashlar shaft, sited to S of house. 2-copper gnomon and irregularly shaped cup-dials to sides.