Resilient and natural prefabricated façades

Natural materials used in construction can help make buildings more sustainable, comfortable, and improve our cities. But what benefits do they bring and how can we measure them? To answer these questions, our researchers are conducting a study that involved the development of two prefabricated resilient façade modules entirely made of natural materials.

The two prefabricated modules of 12 square meters each were designed, assembled and tested in our Facade System Interaction Lab (at the NOI Techpark): one of the most advanced laboratories in Europe for the study of façades in real conditions.

The two prefabricated modules are composed of a load-bearing structure in wooden formwork, filled with different types of straw (insufflated and blocked) and a finish with traditional plasters and based on natural materials. Prefabricated modules are designed for:

• a newly built façade, made with a wooden structure filled with straw bales and insufflated straw, covered with natural and traditional plasters
• a renovated façade, where the prefabricated module (made with a wooden structure filled with straw bales and insufflated straw and externally covered with natural and traditional plasters) is anchored to the existing brick wall.

On the outside, each façade has been partially covered by a vertical green system equipped with automatic irrigation. To evaluate performance, numerous indoor and outdoor sensors were installed that can measure temperature and humidity. The measurements will be used to understand how much these solutions limit the passage of heat, guarantee thermal insulation and ensure internal hygrothermal comfort. At the same time, the effect of green façades on the microclimate is evaluated: the sensors measure how much the presence of plants and the evotranspiration of the leaves can vary relative humidity and temperature, helping to mitigate the heat islands that occur in summer in densely built-up urban areas.

In addition to the energy and thermal aspects, the study also takes into account the sustainability throughout the entire life cycle of these prefabricated façade solutions: from the construction phase to the dismantling and disposal of materials.

The results will contribute to developing construction solutions that combine resilience and eco-sustainability, in response to the challenges posed by climate change and to build more livable cities. The study was conducted as part of the PNRR Return project.