This pilot project provides affordable starter homes with a prefabricated passive circular biobased building shell. UniCasco consists of a drawing set for all components of the UniCasco with which all types of ground-based homes as well as apartments can be built. A prefabricated passive circular biobased building shell meets the climate targets of 2025 due to minimal energy demand and CO2 emissions. Innovation lies in the universal application and that the combination of prefab, passive and circular, has never been successfully applied with multiple homes in the Netherlands. Affordability and scalability are necessary for a concept to succeed for large-scale application. Positive user experience of residents will lead to acceptance of the concept, moreover, this project does not eliminate existing players in the chain but strengthens it. This pilot project aims to promote the affordability, scalability and acceptance of the UniCasco in the market.