In about 1200, the chancel was added (or rebuilt) and a tower constructed to the north, with an arch into the nave. The chancel and tower arches are typical of the early 13th century, with a plain chamfer on the edges rather than complex moulding. The tower arch is much deeper than the chancel arch, indicating the heavier load it had to support.
At some point the north tower was demolished, possibly when the existing west tower was built in the 16th century in the Perpendicular style. At this point the base of the tower became a transept and the accidental cruciform plan of the church was complete. As with many churches, the design evolved rather than being created by an architect.
As an appendix to last month's article on monuments to knights in armour, Thakeham contains the alabaster tomb chest of William Apsley who died in 1527. William is depicted in full late medieval armoural in lines deeply incised in the slab and filled with pitch, a type of decoration unique in Sussex.
One of the main things visitors remember about Thakeham is the slightly perilous climb up the stone path to the church, and the fabulous view from the churchyard.