St Deiniol's Library

St Deiniol's Library is a building dating back to the 17th and 18th centuries, designed with a Jacobethan style and late Perpendicular detailing. Constructed primarily of red sandstone with a medium-pitched slate roof, the building is roughly arranged in an H-plan.

The main south front is symmetrical, with a two-story design and a central, storeyed porch. To the left of the porch is a gabled cross-wing housing the library, while a residential addition balances it to the right. The porch features a coped and gabled roof with a ball finial, and a canopied niche on the first floor contains a sculpted, life-size statue of the Virgin, flanked by two-light mullioned windows with arched heads. A continuous moulded, pointed entrance arch provides access to recessed double wooden doors with decorative ironwork, and the buttress features gablets and moulded bases.

The library range is characterized by four bays with dividing buttresses rising to crocketted finials above a crenellated parapet. The ground floor showcases six-light cross windows with leaded cames, while the upper floor has paired, two-light mullioned windows with arched lights. The left cross-wing incorporates a large, coped gable with a ball finial, along with octagonal corner turrets topped with ogee caps and crocketted finials. The first floor features a central niche mirroring the statue on the main front, flanked by tall, nine-light oriel windows resting on flat buttresses and featuring crenellated parapets and tracery. A small slit-window is positioned in the gable apex. The ground floor includes a central three-light mullioned window, flanked by one and two-light windows, primarily with arched heads, all beneath a continuous label course. Gabled dormers, coped and finialed, project from the east and west faces of this range. A single-story bay is extruded at the intersection with the main block, featuring a crenellated parapet, a central louvre with an ogee lead cupola and weathervane.

The west facade exhibits near symmetry, with gabled and canted bays flanking a storeyed porch and an attached octagonal stair turret to the left. The detailing mirrors that of the south front.

The residential wing, to the right of the porch, has simplified detailing across four bays. A projecting bay is positioned at an angle with the cross-wing, incorporating an entrance on its west face. First floor windows are three-light mullioned, arched-headed, while the projecting bay features two and four-light windows and an angle buttress to the south face. A plain coped parapet tops the wing. The gabled cross-wing here displays a projecting end chimney and flanking buttresses, with two, three, and six-light mullioned windows. A large, canted, finialed ground-floor bay extends from the west face, featuring three nine-light cross windows, with a matching bay to the rear, north elevation.

An unadorned brick extension extends to the east, with simple mullioned windows and a flat roof. A modern, single-story, L-shaped extension is situated to the west of the library range.

Inside, the Library is a five-bay open hall with a complex roof, open to the collar, and supported by arcade posts. This design creates the impression of an aisled hall, despite supporting a gallery that runs along the east and west sides. Octagonal oak columns feature ogee balustrading, and the gallery fascia is adorned with intricate tracery and foliate motifs. The adjoining Divinity Library is a smaller, simpler version of this space, containing stalls designed by H.S. Goodhart-Rendel.