In May 1956, the house was amongst the first of the smaller houses to be opened to the public. In 1958 it was designated Grade 1. In 1948 Knowles had married Ruth Jessie Brooke-Smith, the daughter of the Rev Arther Brooke-Smith. They brought up a large family at the manor: one son, Charles Francis (b. 1951) who later succeeded to the baronetcy, and three daughters, as well as a stepdaughter born to Ruth and her first husband, Dickie Hulse, an RAF fighter pilot killed in action during the Second World War.