Building integrated photovoltaics (BIPVs) are photovoltaic materials that replace conventional building materials in parts of the building envelopes, such as roofs or facades, i.e. the BIPV system serves dual purposes, as both a building envelope material and a power generator. Hence, it is important to focus on the building envelope properties of a BIPV system in addition to energy generation performance when conducting experimental investigations of BIPVs. The aim of this work was to illustrate challenges linked to the building envelope properties of a BIPV system, and to develop and evaluate relevant methods for testing the building envelope properties of…