This villa in Modena is under historic preservation (figure 3). The solution was to build a masonry wall on the room side of the existing wall. The cavity between it and the old wall is insulated with coconut and cork panels, 40 and 60 mm thick, reducing the U-value from 1.75 to 0.25 W/m2K.

New insulating glass windows were installed on the room side of the old windows to preserve the character of the facade. Primary energy demand for space and water heating is reduced 81% from 367 to 70 kWh/m2. The old 104 kW boiler could be replaced by a 35 kW condensing gas boiler. 12 m2 of vacuum tube collectors on the south faqade

of the interior court space help cover this reduced energy demand [4] Fig. 3: Historic villa in Modena IT renovated with

interior insulation (V. Calderaro)