Ventilated rainscreen cladding: Measurements of cavity air velocities, estimation of air change rates and evaluation of driving forces

► Air velocities and temperatures were measured in three different wall cavities. ► Air change rates and driving forces were evaluated with a physical cavity airflow model. ► Average air change rates were high but the daily variations were considerable. ► The driving forces was less than 0.2-0.3 Pa during 50% of the time. ► Wind-induced airflow in the cavities was suppressed in the presence of buoyancy.