Refrigerating cabinets of different sizes and shapes may be manufactured by the use of a single positioning member. Thus, the positioning member has a configuration which is adjustable to adapt to the particular shape of a given inner housing of refrigerating cabinet. When the adjustment is made, the performed housing is fixedly positioned on the thus adjusted positioning member. Previously formed outer walls of the particular cabinet involved then are positioned about the thus positioned housing, with a space being defined between the housing and the outer walls. The positioning member further includes elements which may be employed to partially form a foaming jig. This total unit then is moved to a simplified foaming unit, whereafter the formation of the foaming jig is completed, and insulation material is foamed into the space between the housing and the outer walls.