Interior: C13 triple-chamfered W tower arch. Perpendicular nave arcades of 5 bays: red sandstone double chamfered 4-centred arches on shafts with flat mouldings and embattled capitals. Nave roof of 1869-71 has king and queen post trusses with embattled tie beams and cusped bracing. Boarded ceiling has heavy moulded cornice with quatrefoil frieze. Aisle roofs retain their C18 flat plaster ceilings and moulded cornices. Chancel arch of 1856-7 offset to N of nave: foliate capitals and corbels to wall shafts. Chancel is raised up steps which have encaustic tiled risers; low stone screen wall with foliate panelled decoration. Sanctuary raised up a further flight of tiled steps; wrought brass communion rail (similar to the hand-rail of the pulpit which was added in 1913). Wide chamfered and roll-moulded arch to organ chamber to N. Heavy moulded sedilia and piscina to S, with trefoiled arches carried on polished granite shafts. Chancel roof may be substantially of C16 date: moulded principal beams and joists form panels which have painted bosses at their intersections. It is reputed to have come from Strata Marcella Abbey, although this is unsubstantiated.
Fittings: Pulpit of 1877 to S of chancel arch: stone, with ribbed base supporting canted traceried panelling, with foliate panels. Brass rail to steps added 1913. Font of 1861: traceried octagonal basin on clustered shafts. Reredos of c1870, by Earp: alabaster, Caen stone and marble, with a series of foiled panels, the wider central panel enriched with fleurons, and with a high relief cross. Encaustic tiles in traceried panels to either side. Brass chandeliers in nave were originally fitted in 1776 - removed in the C19, they were restored and returned in 1975. Painted benefaction boards on W wall of S aisle, dated between c1715 and 1946. Relief panel of Royal Arms on W wall, 1802.
Monuments: In the sanctuary: Sir Edward Herbert, d.1594: painted stone wall-monument, paired round-arched panels (containing painted shields in low relief) with text in lower panel, set in an aedicule; Edward Herbert, Second Earl of Powis, d.1848: designed by Sir G.G.Scott: a recumbent effigy in a richly worked embrasure: the alabaster effigy is by Edward Richardson, carved chest with brasses by Waller; the arched recess carved by J.B.Philip. N aisle: Edward Herbert, Third Earl of Powis, d.1891: an alabaster effigy on a chest in a moulded arched embrasure. Various marble wall tablets in S aisle, and a number of brasses, including 2 of C17 date.
Stained glass: Chancel: Shields of arms in NE window, and emblematic design in SE: E window, c1856. SW window of 1900; N aisle: 2 windows of 1875 in medieval narrative idiom, by Wailes of Newcastle; NW window of 1888. E window of nave, neo-medieval narrative in roundels, no date.