The director, who also made The Hobbit trilogy, is said to hang out in the "playground" with superstar pals including George Lucas, Danny DeVito and Steven Spielberg.
Jackson reportedly wanted every detail to be exact and included features like a replica of Bag End, the home of The Hobbit protagonist Bilbo Baggins.
Bino Smith, a set artist who worked with the film maker on The Lord Of The Rings and King Kong, says, "Sir Peter bought a two-storey, 1930s mansion. He got the boys up first to build this giant roof. His eye for detail was such that everything is exactly the same as the movie - but it's liveable. People can stay there. Bag End is underground - you have to go under tunnels to get to it.
"You go to the house, then you go down to the wine cellar and you pull a bottle, and it opens up a door, then you step out a look down this corridor - about 35 metres, we had to create it. Then you go down one part... you come out to a mock 'torture chamber'. Then you pull a book in a bookcase and the bookcase opens, and you walk into Bag End. It's a playground. Steven Spielberg and George Lucas are over here all the time. Danny DeVito is one of his best mates. And it's just for them."