Fiberglass Mesh Reinforced Rendering Mortar: Effect of Fiberglass Reinforcement

In France, buildings’ heating systems represent 45% of the total energy consumption and are responsible for 27% of greenhouse gas emissions. Thermal insulation, including the External Thermal Insulation Composite System (ETICS), has a big impact on energy consumption and CO2 emissions, increasing, at the same time, the thermal comfort of the residents and decreasing their energy bills. The fiberglass mesh-reinforced rendering mortar is used as the external protective layer of ETICS. Many defects may attain the ETICS, including the cracking of the rendering mortar. The cement-based mortar undergoes chemical, thermal, and hygral strains, which, when restrained, cause stress that may attain the material’s tensile strength and cause the mortar to crack. The fiberglass mesh is proposed as a reinforcing solution for cracking. Here, we focus on the cracking development in the reinforced mortar layer using experimental techniques. To understand the crack initiation and propagation in the reinforced mortar layer and the role of the fiberglass mesh as reinforcement inside the mortar, a new mechanical inclined 4-point bending set-up is developed and performed using in-situ X-ray tomography. The latter allows observing the cracks inside the mortar sample, shedding light on the reinforcement mechanisms of the fiberglass mesh and its impact on the initiation and propagation of the cracks.