Designed by James Gillespie Graham in the Perpendicular Gothic style, it has crenellated walls, traceried windows and a tall bell and clock tower at its west end.

[8] Little remains of the original St Rufus building aside from its platform and some fragments of walls, but a number of monuments from the 17th, 18th and 19th centuries survive in its graveyard, which is category B listed.

[10] St Rufus is a large, tall, rectangular building, built in a style described by Charles McKean as "flamboyantly perpendicular", which he contends is typical of Gillespie Graham's work.

[8] St Rufus has been described as "a fine example of a more or less complete and original early 19th century church interior, on a grand scale".

[8] The main internal doorway into the nave from the entrance lobby at the east end incorporates an unusual war memorial.

The outer sides of the recessed double doors bear polished panels, listing men from the parish who died in the First World War; the inner side of the same doors bear similar, albeit smaller and less elaborate, panels recording those who died in the Second World War.

In front of this, mounted at the top of the steps leading up to the sanctuary, is the communion table, which is skirted with alternating open and closed panels with detailed carved tracery.

The gallery is supported by clustered iron columns and two spiral stone staircases at the east end provide access.

The church has retained its original wooden floor, though it is covered in the passages with linoleum for protection from foot traffic.

[8] It bears the initials IO in its upper corners, a reference to James or John Ogilvy who lived at the nearby Milton Tower.

[10] Its five-bay north and south sides are buttressed, with crenellated walls and hoodmoulded pointed-arch windows with transoms and tracery and coloured glass,[10][12] and with wide crowstepped gables at either end.

In the southern face of the bottom stage is a large, pointed-arch hoodmoulded entrance, with chamfered edges and a fanlight above the doors.

[10] In the middle of the east gable is a shallow porch, flanked by angled buttresses and surmounted by a crenellated corbelled parapet.

[10] The building continues to be used as a church,[10] with services held on Sunday mornings, led by Interim Moderator Rev Sonia Palmer.