Sealing of building envelope component joints with watertight, easy-to-install and long-lasting solutions which can be applied in a circular context, is key for the built environment. With this project we aim to strengthen our position in prospective licensing agreement discussions by validating the MULTISEAL technology (patent pending) both in lab conditions and in-field, by demonstrating the performance of functional prototypes in an operational environment and by performing a market study and outreach. The MULTISEAL technology offers an improved and robust watertightness performance, reduced labour costs, and a circular joint system in one product.