The house is protected as a category A listed building,[1] while the grounds are included in the Inventory of Gardens and Designed Landscapes in Scotland.

John White wanted the house to be expanded further, so he came to an agreement in 1892 with a local minister, Reverend Dixon Swan, the heir to the adjacent Garshake Farm lands.

However, he died childless in 1908, and was succeeded by his nephew Dr Douglas White, a London-based general practitioner.

[2] During the Second World War Overtoun was turned into a convalescent home for injured soldiers and locals.

[2] A fire destroyed part of the house in 1948, although there were no deaths, and the hospital remained in operation until 1 September 1970.

[3] The house fell into abandonment soon after Youth with a Mission left the area, but in 2001 Pastor Bob Hill from Fort Worth, Texas, leased the property from West Dunbartonshire Council to use as a Christian centre and tearoom.

This was attributed to supernatural influence, or explained by the dogs being attracted by scents then losing balance on the sloping parapet of the bridge.