The nave belongs to the next period of church architecture - Early English - and was constructed in the first half of the 13th century, perhaps when the first name recorded on the list of incumbents, Joscius of Bilingburg (Billingborough) in 1222, was priest. Presumably the existing nave was destroyed to make way for the new fabric. A quick glance at the columns of the north and south arcades show that there was no attempt at symmetry in the construction.
The final two styles of medieval ecclesiastical architecture - Decorated and Perpendicular - are also represented in St. Andrew's: the former most noticeably in the north aisle and the window tracery of the north transept, the latter in the south aisle and the south transept window stone-work. On the outside, the addition of battlements to the nave and battlements and pinnacles to the tower are typical of the 15th century.
Tops of some of the pillars.