Within this thesis, we discussed the making of families which are the basic building blocks of the information model used within the software Revit. Families are groups of parametric elements that contain information about their properties and their graphical representation.
Among the providers of BIM software applications, we have chosen Revit. Revit is a BIM software package from American corporation Autodesk, intended for the development of building information models (BIM). The BIM process strives towards the unification of information to be within a single building information model which provides all of the information about the planned building and it is the main source for the extraction and entry of all information by all participants within the project. BIM is significantly different from the computer-aided design (CAD) approach to planning buildings, which is why we have compared them to each other and provided basic guidelines required for a successful transition from CAD to BIM.
The thesis focuses on the description of different types of families and determines their usefulness for building a structural model in Revit. After that, a recommended family modelling process is presented, consisting of four steps, namely: establishing the reference planes; appending dimensions to reference planes; the allocation of parameters to selected dimensions and the input of 3D massing, which represents the graphical representation of the family. The emphasis of this thesis is focused on the modelling of families, representing concrete building elements. With the use of practical examples we have shown different ways of making families, which differ depending on the purpose of the family. We then used pre-existing families to demonstrate how one can insert a family into an existing system family or into the structural model.
We find that the use of families within the Revit software is user-friendly as it enables us to quickly design a structural model, given basic knowledge of the program. Compared to traditional CAD software, Revit appears more difficult to use at first glance, because a large part of Revit is based on the parametric approach to design and slightly less to the visual one. However, the use of Revit tools is very well guided, since we are automatically informed of subsequent steps required to be taken, besides the software itself warns us if any errors occur due to the user input. Although the insertion and use of families is simple, the choice of appropriate types of families and their creation is relatively complex. It is necessary to know exactly what the purpose of a family is and in what way we intend to use it. On this basis, we devised the optimal approach to create a family as well as selecting an appropriate type. The modelling of all variations of families has the same approach in principle; however, the process of creation can vary. A well modelled family that has the ability to adapt to any given situation may require more time to develop than a 2D drawing using CAD software. Therefore, we need a lot of experience in the creation of families, based on which we can choose the optimal approach that will meet the structural requirements and won’t be counterproductive to time invested.
We end with a practical example showing the usefulness of importing a Revit Architectural model in a new Revit project for the purpose of developing an architectural template and creation of a structural model. We find that the use of architectural templates greatly simplifies the work, because it serves as a reference when we insert a family in a structural model. One of the major advantages offered by linking a Revit architectural model with a new Revit project is the possibility of automatic control over architectural levels, which enables us to react quickly to any changes in the architectural model by adjusting the structural model.