RE2020 Thermal Study
Saint-Denis, Île-de-France

In Saint-Denis, thermal studies deal mainly with the refurbishment of a large social housing stock and with developments arising from the conversion of major facilities, two registers where the carbon trajectory matters as much as energy savings. The presence of a district heating network across the area is a direct lever on the RE2020 carbon impact indicator, often more effective than further optimisation of the envelope. The intensity of the urban heat island in this sector also makes the treatment of summer comfort a priority, including in renovation.

Summer comfort is the sticking point of the RE2020 in Saint-Denis: on exposed façades, the degree-hours (DH) threshold is quickly exceeded, all the more so in the south of France. Dynamic thermal simulation arbitrates between thermal inertia, solar shading and natural ventilation before the building envelope is fixed.