The late medieval ground plan is typically W Devon, with 2 aisles ending parallel to the chancel. High pointed arches rising from slender granite columns create 5 bays in the nave and 2 in the chancel. The distinctive feature is the outer S aisle, added by the Clothworkers in the mid-15th c.

The Clothworkers' and N aisles are approximately 13' wide and the inner S aisle is 12' wide.