Plas Nantglyn

Plas Nantglyn is a large, two-storey house of a J-plan layout, constructed primarily in the 18th century. It is carefully built from long, roughly-dressed slatestone blocks, laid in a roughly-coursed pattern, and has a renewed slate roof with plain, oversailing verges and a tiled ridge. The chimneys are modern reproductions of earlier Edwardian brick chimneys, featuring oversailing upper courses.

The east-facing garden facade has a five-bay primary section with a gabled single-bay cross-wing projecting to the right. The windows throughout are casements with multiple sections of eight panes, featuring projecting slatestone sills and exposed timber lintels. A modern glazed conservatory has been added in the angle between the main block and the cross-wing. The entrance front is recessed between two gabled wings: the left wing is the northern cross-wing, while the right is a longer service wing. A single-storey outshut extends along the entire length of the main block, with two tripartite windows and an entrance, sheltered by a simple timber-gabled porch with a boarded door. The first floor of the main block has two similar windows. The return wall of the service wing features single, double, and tripartite windows, corresponding to those found elsewhere, along with a further tripartite window in a gabled roof dormer. The rear of this range includes a central service entrance with a cambered head and a part-glazed door, as well as cambered windows to the ground floor left side and to both floors of the main block’s advanced gable on the right. The north side of the cross-wing has two lateral chimneys, one flush and the other with a large projecting, gabled breast. Simple timber-framed oriels, supported on plain brackets, flank this on the first floor, with windows having the same style.

A tall rubble garden wall adjoins the service wing on the garden side.

Inside, the entrance hall features a parquet floor and an Edwardian half-turn oak staircase with shaped balusters. To the right of the entrance hall is an original section of post-and-panel partition, formerly dividing the parlour from the hall. This oak partition incorporates a cross-rail, reflecting an early fashion, and a central Tudor-arched entrance, now blocked. The spandrels of this blocked entrance are carved in relief with the date "Anno Domini 1573." The ceiling is supported by plain joists and a large chamfered main beam. The former hall has a ceiling framed in three ways, reminiscent of more elaborate early storeyed houses, with stopped-chamfered main and secondary beams and similarly-decorated joists. One face of the main beam features a relief-carved inscription, dated "Anno Domini 1574," but reversed. A large fireplace features dressed limestone quoins and a contemporary flat, oak bressummer with complex gadrooned decoration. Two Art Nouveau-style iron fireplaces are located in first-floor rooms. The roof structure dates to the 20th century.