Abstract
1. Through the investigation into operative examples as for the preservation technique according to the part that the Helsinki City Planning Department applied, it was confirmed that a local detailed plan is going to be made while fixing its eyes on a reevaluation and the conversion purpose of the existing building as a sheet of plastic from an initial stage in consideration for a local detailed plan to prescribe preservation requirements. 2. This operative technique brings the flexibility and diversity that met an individual building in a preservation requirements and it is thought that it functions in raising originality and quality of the conversion architecture.