Second stage of north tower and spire possibly C13.
South chancel aisle C15.
Circa C12 church probably comprised nave, chancel, north and south transept and possibly north tower.
In circa C13 a broach spire was erected on the north tower at the north end of the transept.
In circa C15 the three bay south chancel aisle was erected, probably absorbing the south transept and a south porch was added.
South chancel aisle with south wall part rebuilt, C19 2-light window with cusped head and two circa C15 windows with hollow chamfered jambs and cusped heads.
South door with circa C14 2-centred arched opening with moulded jambs.
Circa C15 three bay arcade to south chancel aisle with moulded type B (Pevsner) granite piers, 4 centred moulded arches, moulded bases and caps.
Base of circa C15 rood screen survives although restored and regilded
the uprights are moulded and carved with a floral trail and the restored panels are decorated with blind tracery.
Catacleuse holy water stoup reset in south wall with C15 arch above.
Leger stone of John Mably, 1687 in south porch.
Memorial to Ernest Edward Betjeman of Undertown (qv), father of Sir John Betjeman 1872-1934 on south wall.
Maclean, Sir John Parochial and Family History of the Deanery of Trigg Minor in the County of Cornwall 1879, vol III Church Guide Pevsner, N and Radcliffe, E The Buildings of England, Cornwall 2nd ed, 1970 Sites and monuments Register, Truro, Cornwall.