Arne Vigeland hired two workmen, who used crowbars, hammers and saws to sever the part of the building that rested on the disputed territory. He then dumped the rubble from the demolition onto his neighbours' vegetable patch.
Wenche and Roger Waage, who owned the building, were on holiday in Spain at the time of the attack last year in April, reported Vigeland to the police, and he was this week charged with aggravated vandalism.
The outhouse, that mainly contained tools, stood on a hill on the tiny island of Nesøya, known for having a number of celebrities and members of the Norwegian financial elite among its residents.
Immediately after the incident, Vigeland claimed that the destruction of his neighbour's property was legal, as he owned the land.
"The court believes that Vigeland does not own the area where the cut house stood, unlike what Vigeland has claimed," Sverre Olav Skogrand, the lawyer representing Wencke and Roger Waage told the local Budstikka newspaper.