No, not all the buildings at Grytviken were prefabricated. The prefabricated buildings were brought over from Norway at the behest of the station’s founder, Carl Anton Larsen. Everything, from the workers to the materials, had to be transported by ship.
Larsen’s initial fleet consisted of the whale catcher Fortuna and the transport vessels Louise and Rolf. They carried not just essential equipment but also the prefabricated buildings including Norwegian whaling magnate Christen Christensen’s former house. His home served as the station manager’s villa and the administrative office until it was destroyed in a fire in 1914.
Within about a month, the founding party had cleared land, built housing, installed machinery, set up workshops, dammed a stream for water, and set up a hydroelectric dynamo at the dam.
The most famous prefabricated building at Grytviken is the church which didn’t arrive in South Georgia until 1913. It was designed by Larsen’s son-in-law and prefabricated in Norway then assembled by the station workers in their spare time. It was consecrated on Christmas Day 1913.
Read more about settling South Georgia here.
Christen Christensen’s house, later demolished due to expansion of the workshop was sent to South Georgia on Fortuna in 1904 Manager’s villa and administrative office in Grytviken. It was in use until it was destroyed in a fire in 1914. Source: Vestfoldmuseenes mediearkiv Sandefjordmuseene.