Façade fire testing has been high on the agenda worldwide due to the increased hazard of many occurrences of severe fire spread on façades. There is also international work going on to create a European standard for façade fire testing. In this context it is interesting to clarify what different national test methodologies are based on. This report is a review of the development that led to the Swedish standard for assessing fire performance of façades, SP Fire 105. The review starts from the development in the 1950s with assessing fire exposure from compartment fires and follows further development until 1990s. The fire exposure in the first edition of SP Fire 105 published 1985 was based on two test campaigns including external flames from room fires performed at Lund University during the late 70-ties and early 80-ties. In the early 90-ties the geometry of the air intake in the combustion chamber and the opening under the test specimen was slightly reduced leading to a lower effective thermal exposure of the façade than in the first edition of SP Fire 105. An important observation done already in the 1950s at the Swedish fire laboratory in Stockholm and in the late 1970s at Lund University was that the wind is influencing the test results when doing experiments outside.