The castle was the main residence of the Hunter family but they decided they wanted something bigger for their family so in 1799 they started to build a new home half a mile away overlooking the River Clyde. The Mansion house or more commonly known as the "Big Hoose" was initially built with 2 floors but in the 1930s a third floor was added to the top and can give good views of the surrounding area from the viewing area.
The house comprises of its own servant quarters, tennis court and squash court but in the last 50 years has slowly becoming old with age. Although it is maintained to a basic level dampness is slowly taking over and some parts of the house are now apartments.
On the ground floor immediately inside the main entrance is the Oak Hall, this is not surprisingly all made of oak and is a nice area of the building and access to the rest of the 2 main floors is via a grand staircase.
Each of the rooms have a different name, some are names after villages in the area, others of hills and farms and others represent the room itself, be that the smoking room or the white room because of its white carpet.
Some of the room names are: Kilrusken, Ardneil, Campbelton, Goldenberry, Sannox, Keppel, Wemyss, Largs, Crosbie, Carlung, Ailsa, Arran, Bute, Fairlie, Cumbrae, and Kelburn