Volume rendering is an illustration technique for visualising different 3D measured data or 3D simulation data interactively on screen. This paper introduces a method that overlays several types of volume data on an architectural surface model. This complex calculation takes place on the graphics card using hardware-accelerated shaders. An implemented software prototype entitled ìVolumeRenderingî is introduced. In addition to interactive visualisation, the objective was to create a user-friendly interface. Synergies and new evaluation possibilities arise through the overlay, e.g. of different measuring techniques, with a surface model. Finally the use of the software prototype is illustrated using examples from our interdisciplinary research project.