The building sector accounts for around 40-50 % of the energy consumed in developing countries and contribute over 30 % of CO2 emissions. In Cameroon, the electricity access is less than 5 % in rural areas against 50 % in urban areas. All sectors combined the Cameroonian final energy consumption amounts to approximately 5235 kilo-tonnes of oil equivalent (Ktoe) and 73 % of this energy are assigned for residential use. This energy can be considerably reduced with the development of low energy buildings using Building Integrated Photovoltaic (BIPV), since it has been proven an effective solution to achieve significant energy savings and conservation. However, photovoltaic (PV) panels produce a substantial amount of heat, while generating power. Consequently, BIPV’s concept, where the photovoltaic (PV) panel is integrated on the building envelops has significant influence on the amount of heat transfer through the building fabrics, and could affect the indoor air temperatures and the comfort of the occupants, since, it changes the thermal resistance of the building envelops. In this paper, the effect of the BIPV on the indoor air temperatures and humidity (IATH) of multiple storey buildings under the tropical climatic conditions of Yaoundé, Cameroon has been modelled and analysed. Two cases of BIPV made of 290 m2 area of PV have been considered, i) roof integrated and ii) façade integrated. In addition, building orientation, roof pitch and the building materials are also been explored and optimised to provide the best combination. It has been observed that for both cases, BIPV increases the building’s indoor air temperature by about 4 °C, when compare to a building of the same size without PV integrated.