As carbon dioxide emissions are still growing, and the building sector is highly responsible for. Because the existing building stock dominates against the newly built and the operational energy consumption is double that of the embodied energy of building materials, renovation is the key area that can reduce the CO2 emissions effectively. This study presents the implementation and results of the REHOUSE project, focusing on a Hungarian demonstration site—a late 19th-century dormitory in Budapest. There were developed eight renovation packages from which three was inmplemented in the Hugnarian demo building. The Adaptable Dynamic Building Envelope provides a framework for the outer surface of renovated buildings, allowing for the integration of Intelligent Window Systems and activated cellulose insulation. . The original wall and window thermal transmittance were reduced from 1.32 W/m2K and 1.4 W/m2K to the values of 0.24 W/m2K and 0.5 W/m2K respectively. As a result of the renovation, the Intelligent Window System saves 3.6 MWh annually, while the Adaptable Dynamic Building Envelope and its integrated insulation contribute an additional 16.62 MWh in annual energy savings. . Besides these the installed PV systems on the façade and on the roof produce 36.57 MWh energy every year. The annual energy balance of the building was reduced to half of the original. The project demonstrated the importance of renovation and the significant potential in environment protection in this way.
Horváth et al. (2026) studied this question.