Modularisation is a critical element in the industrialisation of the construction industry. This is also a key precondition for prefabrication. Within modular construction, projects typically require adaptations to each module to manage the requirements of the customer, regulatory bodies, the construction site, and the specifics of the module placement within the building cause. The basic idea of configurators is to provide an interface for product choice management and a structured rule set for managing these customisations within the requirements. In this study, we examine the key demonstrable features of a configurator in the concept development and design phases of a house-building project. We organised a dedicated workshop for the development of the configurator. The workshop was held with eight participants from the construction industry across construction design disciplines and eight research-oriented participants. After the workshop, participants from the industry were sent a feedback form that allowed experts to highlight their individual views. Each industrial specialty highlighted its needs, which can be summarised through flexible layout plans that automate certain aspects of design. These plans need to be evaluable though KPIs’ and reports, which take into consideration layout distribution, costs, habitability considerations, and environmental impacts. The configurator was recognised as a potential way of incorporating these different requirements while considering the needs of the prefabrication process.