This paper presents the experimental setup, a computer model, and simulation results of a recent Ph.D. project that focused on the effect of convection in lightweight exterior facades on moisture transport. First, the paper presents measurements of air velocity in the wall cavity by tracer gas and thermal anemometer. It is found that tracer gas can be used for air velocity measurement. Secondly a computer model is validated against measurements. Finally, using the computer model, a set of different yearly simulations with weather data from a design reference year were used to study the effect on cavity moisture levels of (1) insulation thickness, (2) presence or absence of vapor barrier, and (3) the degree of cavity ventilation.