Abstract: The present invention relates to a building and a method for assembling a building. The building comprises an external framework 10 with at least three external walls connected with a floor structure and a roof structure such that a space is formed within said framework, the external framework further comprises a support system for each floor, and at least two modules 1, wherein each module comprises four walls 2a,2b,2c,2d, a floor 4 and a roof 3, wherein said at least two modules are mounted in the space in said external framework, which said at least two modules rests on said support system 15, such that an air gap of at least 150 mm is formed between two adjacent walls of said at least two modules.