Summerhouse at Plas Dinefwr

Summerhouse at Plas Dinefwr

This is a castellated country house built in grey-shale with pale sandstone dressings and redstone patterning. The entrance front is symmetrical with three storeys and basement, featuring splayed angle turrets and a massive central porch. The parapet is corbelled and openwork with quatrefoil design; the turrets are machicolated and crenellated with inset red stonework. Five top-storey windows have shouldered and chamfered openings set into segmental outer arches with paired casements. The lower floors have two-light timber cross-windows with pointed relieving arches, and heraldic shields decorate the tympani of ground-floor openings. Basement openings have corbelled sills over segmental arches. Low coped parapets flank a robust Gothic porte cochere with tall chamfered openings; the outer face is tripartite with hoodmoulds and quarter-round shafts. An inner doorway has a trefoil-headed surround.

A single-storey extension with attic, added in 1896 to the left, features decorative loops to its side elevation and a link corridor. The hipped slate roof has a panelled parapet, five windows with pointed relieving arches, quatrefoils and frames matching the main structure.

The west elevation is more elaborate, with fine tall chimney stacks topped by crenellated and corbelled cornices set behind the parapet. It is slightly asymmetrical, with openwork corbelled balconies to the first floor left and an elaborate two-storey Venetian Gothic stone verandah to the centre. Side walls are topped by tall pinnacles and flying buttresses, with an openwork parapet over a six-light glazed balcony featuring inset red dressings to quatrefoil tracery. A three-bay arcade to the ground floor is rib-vaulted with quatrefoil columns and foliage bosses. A tall boundary wall runs from the south-west corner of the house and returns west to enclose the south side of a walled garden.

The plan-form includes a thick spinal wall and large parts of exceptional late 17th and 18th century interiors survive, though some later alterations have been made. The entrance hall has a columned Doric screen and a 19th-century ribbed and bossed ceiling; the right-hand wall has been rebuilt with a modern concrete beam. The old dining room to the right retains a splendid 17th-century coffered ceiling enriched with low plaster relief mouldings including guilloche, acanthus and egg-and-dart; it has dado rail, architraves and raised-field door panelling, though the chimney piece has been removed. The old drawing room to the rear features rich 17th-century plasterwork including a pulvinated frieze bearing rosette bands, a coffered ceiling patterned as before with a centre oval containing bay leaf design, lugged architraves, and panelling with foliage sprays on plain fields. A 1911 dining room occupies the rear.

A splendid 17th-century openwell timber staircase with some 19th-century additions has an open balustraded handrail and plaster foliage patterns to the soffits, with fine early classical detailing to strings and cornices. Nineteenth-century rose pendants and a finial to the newels (some inserted) are present. A half-landing features a ribbed archway to a Gothic balcony with glazed room and ornamental iron brackets. Nineteenth-century top lighting illuminates the staircase, with foliage trails to the coffering.

Upper floors contain good-quality 18th-century fittings including panelled dados, lugged architraves, low-relief plaster ceilings and closets within angled turrets. The north-east bedroom has a console cornice and is reached diagonally through the thick spinal wall; it is almost polygonal in shape and links en suite to a room overlooking the main porch. This room has a very rich coffered ceiling with foliage and guilloche cornice band, and a large bed recess. The topmost floor sits beneath an oak trussed roof with morticed principals (for purlins of the former roof with dormers). A remarkable bedroom here retains a deep Georgian bed recess with a wide, flattened and keyblocked arch.

The stone-flagged basement contains vaulted cellars, a strong room and slate shelving to the wine store.