This paper presents the results from a 4D modeling study in which 4D CAD was used to compare two different construction methods for a cast in place concrete structure. Evaluating construction alternatives in a virtual environment is considered to be an effective and cost efficient way to introduce and evaluate innovative construction processes and products. Results from the study show the potential of using multiple virtual prototypes, but also show limitations regarding required modeling effort and evaluation of results. Im-provements are suggested that facilitate and partly automate the 4D modeling process. Evaluation of the out-come of 4D models can be improved by extending the graphical outcome of the modeling process with a vari-ety of analyses. Research and development is needed to quantify results from 4D models, in order to allow comparison of construction alternatives on a range of different criteria.