The building envelope, the interface between indoor and outdoor, plays a major role in influencing the impact of outdoor climate and controlling the indoor thermal conditions; hence, maintaining the health and productivity of building occupants. The building envelope also significantly influences indoor heating and cooling loads and therefore building energy consumption. Both electric power and useful thermal energy can be obtained from building-integrated photovoltaic systems (BIPV/T), which have the potential to reduce energy consumption of buildings. Double-skin façades (DSF) are well-adopted for enhancing energy efficiency and improving indoor thermal comfort. Thus, this study investigates the overall performance of a combination of BIPV/T and DSF using simulation analysis, hence identifying the optimal design solution, which was embodied in numerical assessment of indoor thermal comfort and energy consumption for a commercial building. In the study, different BIPV materials (amorphous silicon PV, dye-sensitized solar cell and Perovskite-based solar cells) were considered as the exterior cladding of an office building. The performance assessment involved three climates in Australia – from hot humid to cool temperate – represented by the cities of Darwin, Sydney and Canberra respectively. The air cavity of the BIPV/T-DSF was alternatively assessed in non-ventilated, naturally-ventilated and mechanically-ventilated modes of operation, while a sensitivity analysis determined the most influential design parameters to be optimised. The study found that the perovskite-based solar cells was the optimal configuration achieving ideal performance on indoor thermal comfort and energy saving. In Darwin, the optimal design solution was naturally-ventilated BIPV/T-DSF facing 50° north-by-west for all year round, with the use of thermal transmittance of the DSF’s internal window (Uin) of 3.1 W/m2.K and solar heat gain coefficient of the DSF’s external window (SHGCout) of 0.44. In Sydney and Canberra, DSF facing due north was the optimal direction for the both locations, while non-ventilated and naturally-ventilated modes being utilised during the cold and warm periods, respectively. Moreover, for Sydney and Canberra the optimal values of Uout (thermal transmittance of the DSF’s external window) and SHGCout were 3 W/m2.K and 0.44 respectively, while the optimal Uin was 5.16 W/m2.K and 1.4 W/m2.K respectively for Sydney and Canberra.