The Ministry of Church Affairs did during the 19th century provide a selection of designs for vicarages. This residence is assumed to be based on a design by the architect H.D.F. Linstow from 1835, which was modified by J.L.B. Sverdrup. It's often described as the Sverdrup-Linstow plan. Brønnøy Vicarage has a slightly smaller footprint and there are variations in the way the rooms are organised. The dormer, which was added some years later, made room for more bedrooms in the large attic.
Originally there were two entrances at the back of the building, one to the vicar's office and one to the kitchen. The main entrance was moved to the east side, and in the early 1990s it was renovated and given a two-column portico and an empire-style door with a transom window.