The Old School, including attached walling

The Old School, including attached walling

This is a limestone rubble building of mixed construction dates, with the original house built in random rubble while later additions are of squared and coursed rubble. Bath stone dressings appear on late 19th-century features, and the roofs are covered in Welsh slate. The building comprises two storeys, with an attic contained only within the original house.

The original house occupies the centre of the south-east elevation. The original entry was probably in the south-west gable, which now features a late 19th-century transomed 4-light window with dripstone mouldings ending in square stops, a similar window above it, and a blocked slit window to the attic. Moving along the front elevation from the south end, there is a blocked rectangular opening to the ground floor, followed by a projecting bay (similar in style to those found at the Old Swan Inn, Cherry Tree and Tudor Cottages). This bay contains a late 19th-century 4-centred doorway on the ground floor, an early 3-light mullioned first floor window with dripstone and single light windows to each return, and an early 2-light window to the attic gable with single light windows to each return. Three further sections of the front elevation each contain late 19th-century 3-light transomed and mullioned windows on both ground and first floors, without dripmoulds on the upper floors. The steeply pitched roof carries three roof-lights and a ridge ventilator. A hipped bellcote with ball finial sits at the north-east gable end.

The rear elevation of the original house contains stair and garderobe lights, two gabled dormers, and a rear lateral stack. A projecting classroom wing with a tall chimney and 3-light window in the gable end extends from this elevation.

A lower addition to the north-east end, probably dating to an early period and incorporating existing old walling, was converted to a headmaster's residence in 1873. From the south-west facing side, this section features a gabled 2-light dormer and a doorway with a plaque inscribed 'LLANILLTYD/FAWR/1873', marking the school entrance and staircase location. A second similar 19th-century doorway stands nearby with a single light 19th-century window above it; both doorways have plank doors and dripmoulds. A canted bay window with slate hipped roof and sash lights arranged 1 over 1 + 2 over 2 + 1 over 1 appears next to these, accompanied by a 2-light sash window to the first floor with 1 over 1 panes and dripmoulds. Gable and rear slope stacks serve this section.

The rear elevation of this addition contains a gabled wing projecting behind the first door (housing the staircase, lit by 2-light windows), two 2 over 2 pane sash windows to the house, and further windows in the gable end.

A set-back later 19th-century or later stone wing extends from the south-west end of the original house, featuring three mullioned windows with dripstones. The return has 2-light windows on each floor, leading to a single storey gabled classroom with a 5-light mullion-and-transom window.

At the entrance stands a low 19th-century dwarf wall with late 19th to early 20th-century low iron railings and stone gate piers.

The interior contains a ground floor fireplace on the north-west wall of the north-east room, decorated with roll and hollow chamfer mouldings and a row of seven trefoil panels above the fireplace arch. An arched staircase door to the north-east provides access to a removed staircase, now partially blocked. On the first floor, a blocked Tudor fireplace survives in the north room, and two possible garderobes are located in the north-west wall of the south room.