 He moved the Capell family seat from Hadham to Cassiobury, commissioning a lavish reconstruction of his father's Tudor mansion from the architect Hugh May.The new house was built c.1677–80 and laid out on an "H" ground-plan, popular during that period, incorporating the original north-west wing.As he had already done at Windsor Castle, May teamed up with the wood carver of the day, Grinling Gibbons, and the painter Antonio Verrio to create a sumptuous interior.