The actor has submitted a detailed planning application for work on the £8 million property in Highgate, North London.
According to the Daily Mail, Law claimed that he wants to "return it to its original splendour".
Law's architects Richard Keep insist that the changes are justified as the current design "does not reflect the original layout" of the building. They have suggested that "all fixtures and fittings and finishes are modern and in need of an upgrade", preferring a style closer to that of the original 1823 design.
Law is also believed to want a state-of-the-art gym, solar panels and a steam room.
The house will be a bachelor pad for Law who split from Sienna Miller earlier this year. Miller is now rumoured to be dating actor Tom Sturridge.