This work describes an information system that uses complex calculation in civil engineering. In the procedure for calculation of foundation grids, soil is treated as homogeneous, elastic and isotropic halfspace, described by two parameters: the elasticity module and Poisson’s ratio. The process is based upon the force method. In order to obtain a complete formal object-oriented specification of the system for calculation of the foundation girder on an elastic ground, the Object-Oriented Transformation Methodology is used. This methodology separates the database from the programs by forming a unique base object that contains all data stores from the system. The functioning of the system is specified by the communication between the base object and the remaining objects, which can be either embedded objects or application objects.