The original Finlaystone House (14th century) was extended in 1760 and again in 1900 by Sir John James Burnet on behalf of George Kidston, the great-great-grandfather of the present owner. The house embodies centuries of tradition and heritage. It has been a home for three families over six centuries and is currently home to the Chief of the Clan MacMillan and his family.

The Finlaystone shown on a map in 1662 would have included Dennistoun's Tower.

"At one corner of the square stood the tall massive round tower, probably the most ancient part of the building. In taking it down it had to be blasted with gunpowder like a rock, so thick and hard were the walls." - Alexander Gibb, "Much About Kilmacolm", 1872.

The present Billiard Room perhaps stands on the original Dennistoun foundations.

The Finlaystone as known by Robert Burns was not that which was described in 1710. The fashionable architect John Douglas had been commissioned in 1746 to knock down some buildings round the court - the "bailey" of the old castle - and to replace them with a new house.

While the north wing incorporated the remains of Dinniston's Tower, the south wing was based on what was then called "the old house". The central part of the modern house is that built by Douglas; and the present Library was the main room in his design. A kind of Alcove in the Middle with a Venetian Window in it was particularly admired by a visitor in 1750, the year this picture of Douglas' house appeared on a map.

Possibly late 18th century, in place of Douglas' colonnades and pavilions, solid extensions were made to his "new house" in the same style. With the addition of the kitchen wing and the tower for water storage, put up by the new owners in the 1860s, the facade of the present house was in place towards the end of the century.
 
 

 
When, after renting Finlaystone for twenty-five years, George Jardine Kidston finally bought it in 1897, he engaged John James Burnet, a leading Glasgow commercial architect, to give the house some style and fit it better for his family and for entertainment. Though Glasgow-born, Burnet had studied at the Institute des Beaux Arts in Paris. So, though local, he was not parochial.

The ground floor was developed mainly with men and sport (notably fox-hunting) in mind. It was enlarged to accommodate a porch, a cloakroom and a billiard room. A top storey was inserted in the roof to provide nurseries for grandchildren and a flat for the butler. To balance the new addition to the ground floor, Burnet added a heavy cornice and carved stone crest at the roof line.

Perhaps the most striking feature of Burnet's interior is the pair of pink marble pillars with a mythological beastie at their base. This was Burnet's favourite way of ending a stair rail.

George Kidston's sister, who came to control the household after his wife died on the birth of their ninth child, ruled on the first floor - a more feminine place of entertainment. The drawing room with its baroque door-case, white marble fireplace, high ceiling, and bow window overlooking the Clyde, is possibly one of the finest of Burnet's interiors. Because of his work the house is designated 'historic'.

The kitchen has been restored to what it might have been in 1910, and is open to visitors as part of a tour of the house.