By 1937 the McCaughey building was considered inadequate and the then headmaster, Philip Le Couteur, pushed for the construction of a new building for junior education and he is seen as the founder of the present day Wyvern House. The Old Newingtonian architect Lt Col Alfred Warden designed the building and it was inaugurated on 7 October 1938. A major benefactor to the project was Fred Cull and he unveiled a commemorative stone which read: "This House was erected by those who desire for boys a fuller life." The first Wyvern boys started on day one of the new year when an old boy, Sir Percival Halse Rogers, was invited to open the front door with a specially-made gold key.
