The thermometer shows two small degrees at the end of November in Grenoble (Isère). But in the new Haute-Bois building opened this year, residents don’t have radiators. “When you look into the rooms, it seems that something is missing! However, one does not die from the cold, confirms Mohamed, a 29-year-old tenant. The big advantage is that I no longer pay for heating. We can’t say no to the price increase! »
To keep at 19°C, the secret of this building of 56 social housing units lies in the all-wood construction. The material is 12 times better insulating than concrete. 30% is in Isère and the Vosges, the rest in Austria. Zinc coating will protect it for 50 years. It also benefits from a dual airflow system that prevents 90% of energy wastage. “We extract heat from shower water in particular, every calorie is valuable,” explains architect Jacques Félix-Fort.
Twice as tight as standard
If wooden houses already exist, then their use for a nine-story building is unprecedented in France. Enough to work hard on its architect. “Because this is the first case, we burned down two test floors to show that wood resists fire just like concrete. We also did seismic testing because we are in a 4/5 risk zone,” lists Jacques Félix-Fort, accustomed to extreme structures such as the Aigle shelter at 3,450 m, which inspired this “passive” building. ».
“The logic is the same. Haut-Bois is twice as tight as standard. Wood is thinner than a concrete wall, so thicker insulation can be used. Additional construction costs (€1,750/m2 compared to €1,400/m2) are to be fully offset by future energy savings.
Source: Le Parisien
