[1] The tower is a simple rectangle on plan, measuring about 7.80m east to west by 10.70m transversely, which stands to the level of the corbelling of the four angle turrets, now gone, about 12.0m high; on its south side, the chimney stack and part of the gable remain.

The only remaining ornamental feature is the pediment above the main entrance, inscribed with the initials of Margaret Hamilton and John Wallace.

Extant photographs and plans indicate that the courtyard supported various subsidiary buildings, including a wing attached to the southern wall of the tower, now gone.

The entrance doorway opened into a small passage, from which the two apartments could be formally accessed and where the circular stair to the upper floor started.

The hall differed from the great majority in Scottish castles, the ceiling having been flat and low instead of the usual loftily arched form.

It is evident from the existing plans of the second floor that it had been divided into two apartments by a light partition starting from between the doors of the two garderobes in the south wall.

The corner turrets had been roofed, and checks previously existed for small doors at each, and iron crooks for the hinges.

A large gutter, made of stone hollowed on the surface, formed the junction between each turret and the main roof.

These include IW and MH on the pediment above the main entrance, IH and IC 1680 above the lintel at the head of the stair, and WO 1699 on the battlements.

Accordingly on 9 July 1647 a grant under the Great Seal was made to John Wallace of the right to do so, hence the Hamiltons of Barr.