Exterior
'The building is constructed in lias limestone, quoined mainly in the same material, though the tower is quoined in Sutton stone. Sutton stone was also used for the earlier openings, teamed with a limestone of similar appearance but more tractable character, identified by Halliday as Dundry stone: the later medieval openings are in sandstone, and Bath stone was used for the 1899-1905 repairs.' (Glamorgan/Gwent) Welsh slate roofs.
'The church consists of two sections, the eastern church with nave, two aisles, chancel and W tower, and the W parochial nave which has a S porch with parvise, and a large chapel (Galilee), now ruinous, built against the W end, with an upper floor at its W end; there is also a small room, now used as a store, to the N of the chapel, which is believed to have been a sacristry.' (Glamorgan/Gwent)
The entrance is into the West Church which will be first described. The doorway, which is reached through a porch with a recessed chamfered 2-centred arch of C13 type, is a plain round arched Norman one with a Victorian plank door. The parvise above is lit by a single trefoil headed light over the archway, but there are five small square openings (putlog holes) rising diagonally on either side up into the gable. Battered base with corner buttresses, very steeply pitched gable. The right hand buttress is corbelled out to the upper floor, which seems to have been done to accommodate a pre-existing building, since demolished (shown on a plan by Halliday).
The south wall of the nave shows stonework of different characters said by Halliday to be evidence of the incorporation of part of a pre-Norman building, with possibly two rebuildings above. To the left of the porch is a 3-light arched Perpendicular window with cusped lights; to the right is a 3-light square headed Decorated window with cusped and trefoiled heads, and to the right again a 2-light C13 one with equal trefoil headed lights. The north wall has a window similar to this latter one, but a Victorian replacement. The dripcourse on the west side of the tower above the south slope of the West Church roof suggests that the roofline has been lowered, whereas the north pitch appears to be original, but it is difficult to see any difference internally.
Ruined C13 west Galilee building, with its former chapel, later probably a chantry chapel (Sir Hugh Raglande's chantry). This has a C13 window with tracery missing in the west gable which lit the upper chapel and large archways, once windows (see surviving evidence of where the cills were), flanked by buttresses in both north and south walls to the undercroft; two of these medieval buttresses have been ripped off at some period leaving large scars. The evidence suggests that this was converted to a barn at some stage after Dissolution, note the opposed doorways, but it is unknown when it became unroofed. The interior of this section retains, in the upper part of the east wall, a multiple-moulded niche with a dripmould over (a later addition for protection) and, to the right, an ogee headed piscina. west window; two stone staircases at the west end and a further one at the north-east end leading to the stair to the upper floor of the Sacristry entered through a small 2-centred doorway, with a larger 3-centred arch beside it into the west church.
Probably C15 Sacristan's lodging of two storeys against north wall. This has small square headed windows, a steeply pitched roof and a gable chimney.
The tower is over the west end of the east church. Although, internally, the crossing is Transitional and therefore probably of c1200 what can be seen on the outside appears C14 with a probably C16 castellated parapet. Two stages above the roof with a single light with cusped head on the north and south faces, the one on the east face is now internal. Pairs of trefoil lights to belfry; corbel table; castellated parapet with cross-eyelets.
East Church comprises nave, chancel and north and south aisles of later C13, the massive stone arcade piers built on the lines of the walls of the Norman or earlier chancel, but see History. Two-light aisle windows with Geometric tracery, three on either side, the south-west window now a door, buttresses of 1905 between the windows on the south side added to support the flying arches within. Clerestorey windows, partly set into the aisle roofs, two on the north and one on the south, although Lambert found evidence for a second in 1888, 2-light Perpendicular windows, the northern ones seemingly Victorian. Three-light east and west windows to both aisles. Halliday suggests that the Early English east window of the south aisle is the original east window reused when the aisle was shortened.
Chancel with four lancet windows with trefoil heads on north side; restored Perpendicular east window with two large lights, each with two smaller ones within, panelled head and dripmould over. Probably C15 2-light ogee headed windows in blocked arcade arches on south side. Priest's door and attached early C19 railed enclosure below. The north wall with coursed and squared stones is largely part of the restoration, as is the upper part of the east gable with its coping and apex cross.