He employed a joiner Evan Lucas to supply panelling and carve ornaments including leopard's heads for the hall and gallery.
By the 19th century, the building was falling into disrepair, but a new occupant in 1818, Sir John Shelley-Sidney, uncle of Percy Bysshe Shelley, gained ownership of the property.
[6] His son Philip Sidney, 1st Lord De L'Isle and Dudley, continued the restoration.
[6] He was one of only two men who held both the Victoria Cross and membership of the Order of the Garter; he was created 1st Viscount De L'Isle in 1956.
[6] Many members of the family are buried or commemorated in the Sidney Chapel at St John the Baptist, Penshurst.
[7] It is possible to see in the house the evidence of occupation over its 670-year history: One notable element of the property was the Sidney Oak tree, estimated to have grown for more than 1000 years.
[9] An oil painting depicting the tree and the Penhurst property was gifted to the Victoria & Albert museum in 1857, where it is still housed.