Slate roofs with ridge tiles and gable ends.
Plan: The original C12 church would have been cruciform, with nave and chancel in one and transepts to north and south.
In circa mid C15, the south aisle with south porch were added.
The north gable end has 3-light window, possibly C14, with three 2-centred arched chamfered lights, the central light taller.
C17 studded plank door with strap hinges
C15 3-light Perpendicular west window with cusped lights, 4-centred arch, hood mould and relieving arch.The third stage has C15 3-light Perpendicular bell-openings with cusped lights, 4-centred arches and hood moulds with pierced wooden louvres.
The west end has similar C15 Perpendicular window with some C19 restoration to the mullions.
The south side has four C15 Perpendicular 3-light windows, with 4-centred arches and hood moulds, some C19 repair to mullions.
On the right wall is a slate tablet to John and Katherine, with verses, 1696.
Inner doorway has wave-moulded surround with 4-centred arch with hollow-moulding, recessed spandrels with carved leaves
fine C17 studded door with fleur de lys strap hinges and sanctuary knocker.
The nave and chancel are roofed in one, with unceiled wagon roof, of circa early C19, with moulded ribs and wall-plates, and carved bosses
The tower arch is 4-centred, with triple shafts with carved capitals and bases
2-centred arched doorway to the tower stair with C17 studded plank door with fleur-de-lys strap hinges.
5-bay south arcade, with Pevsner A-type piers with carved capitals, 4-centred arches with convex mouldings.
The chancel has C19 aumbry and piscina, with C19 carved wooden reredos in Gothic style
The south aisle has C15 piscina with 4-centred arch and similar holy water stoup by the south door.
C15 rood screen with Perpendicular style carved panels and tracery
C18 alms box in south aisle, with carved oak leaves.
C17 stocks in south porch.
In nave: a marble monument to John Couch Adams, who discovered the planet Neptune
Glass: the east window of the chancel and the south windows in the aisle retain fragments of C15 glass, with Christ crucified, St Christopher and St Catherine and instruments of the Passion.
The east window in the south aisle has late C19 stained glass with the Virgin and Child, St George and St Sativola (the Latin rendering of St Sidwell).