Examining different team dynamics and under- standing collective activities in home environments are two important challenges for ergonomics and its related fields. This article focuses on collective activities within home/ building conceived as semi-open spaces (opening up opportunities whilst at the same time imposing more or less radical limits to collective activity) and discusses how orchestral formats (radically separating conceptual/physi- cal and temporal axes) provide alternative perspectives for qualitative research. To do so, we leverage on the creation and use of MUltI-SCOre Format (for MUSICOF) in two previous in-depth studies of households and firemen. Drawing on a reflective analysis of our research practices, we describe how MUSICOF provides benefits when the researcher/practitioner has to cover a large concep- tual/physical space, synchronise each basic unit of the collective activity, analyse activity at different levels (cognitive, social and spatio-temporal), characterise spatio- temporal arrangements and zoom in/out different degrees of abstraction of the analysis. It allows one to articulate multiple data and categories on a unique temporal axis, to formalise any type of arrangement of collective activity within space and time, to access all the required data on a single document where all the basic units are synchronised and to create either detailed empirical or synthetic formative models. After the demonstration of these benefits and some challenges, we discuss the perspectives and limits of this paper in order to equip studies of collective activity’s dynamics more consequentially regarding semi- open spaces, situated/distributed cognition, cognitive work analysis and scenario-based design.