Multi-storey residential buildings in cross-laminated timber are emerging as a sustainable and profitable option with industrialization possibilities, that open the way to new paradigms in construction. In this new building model, the standardized modulation results in an efficient strategy to integrate design and manufacturing platforms. However, the application of this strategy requires the study and development of methodologies that achieve the necessary design flexibility to obtain adequate levels of production and customization. Based on this, this work analyzes the modularity conditions observed in five buildings built between 2002 and 2016, in order to study the standardization criteria implemented. To achieve this, an analysis is made of the underlying modularity in the design and the conditions of variation or repetition presented. In this sense, the use of different modularity criteria was observed between the first experiences developed and the most recent buildings, given by the technological progress of recent years. The research allows us to approach the understanding of the modularity conditions associated with these buildings, as a contribution to the development of methodologies that optimize the design for manufacturing and assembly.