Abstract Historic building heating and, in particular, church heating represents a challenging task because many objectives have to be reached simultaneously, such as occupants thermal comfort and optimal internal climate suitable for the preservation of fragile building components and artworks. Moreover, current requirements for sustainability impose to make efforts, where possible, to minimize the amount of energy needed and the consequent environmental impact. Innovative solutions are currently under research and development and are mainly based on electric radiant surfaces. The present work represents actually a detailed performance analysis of a novel hydronic high-efficiency pew-based heating system coupled with a ground-source heat pump. The system was specifically developed for the above-described application field, with particular reference to the Basilica di Collemaggio (L’Aquila, Italy), a church of worldwide relevance currently under restoration. In detail, within the work a three-dimensional CFD analysis of the heating solution was carried out considering as application field a virtual test room containing two benches with three virtual sitting manikins. Heat exchanges between the human body surfaces, the room environment and the heated benches were simulated in order to assess the whole performance. The results show that the air temperature in the room is not significantly influenced by the heating system, but the heat is directly radiated to people, ensuring comfortable conditions and contributing to artworks preservation.