In 1900, Algernon George de Vere Capel, the 8th Earl of Essex (1884-1966), sold the Hall and the accompanying land to a London merchant, William Minet, who set about restoring the hall. In 1948, Hadham Hall was sold to the Hertfordshire County Council, who converted the building into a school. The school closed in 1990, and merged with the Margaret Dane school to form Birchwood High School