The growth of the IoT (Internet of Things) offers a large number of opportunities for new product development. The adoption of IoT technologies improves the operational efficiency of products and their interaction with humans. The variety of sensors and communication protocols, the increased number of cloud infrastructures and services, not forgetting security challenges induced by the IoT technologies lead the designers to make complex choices in the configuration of an optimal IoT solution. Modularity and design for configuration represent an efficient solution for the design of products adopting the IoT technologies. This paper applies the model of configurable product design, conceptualized as multi-layer fuzzy models, to the product integrating the IoT technology. The layer models are the fuzzy product specification layer, the fuzzy functional network layer, the fuzzy physical layer, and the fuzzy constraint layer. The model discerns the consensual elementary solutions that create common ground for moving toward a global solution. The case study shows the configuration of a connected houseplant sensor.