The OpenGL™ rendering engine, which comes with the Windows PC operating system, allows display of room geometries, which have been modeled for room acoustics prediction purposes. Viewing a 3D geometry as a surface geometry rather than as a wire frame, allows easy detection of geometrical errors like holes and missing surfaces. However with an appropriate surface olouration it is also possible to view material properties. This paper suggests that the acoustic reflectance of acoustic materials is converted directly into a visual representation, where red represents low frequency, green represents middle frequency and blue represents high frequency reflectance. In this way total absorbing surfaces appear black whereas total reflecting surfaces appear white and indeed surface colours, which display acoustic reflectance appears in a visually plausible way and it is very easy to read the acoustics properties of the surfaces in a room model.