Nowadays architects commonly use the ‘coupled space concept’. Examples are mezzanines, half-open office spaces and exhibition rooms. Because of the need to meet acoustical standards, the need to predict sound pressure levels and reverberation times for this category of spaces is ever growing.The transmission of sound from one space to another depends on design decisions like position, shape and dimensions of each of the interconnected spaces and of the “gap” between the spaces. In this paper the suitability of ray-tracing based simulation tools for the prediction of actual sound pressure levels and reverberation times in coupled spaces will be discussed.