Mix design and characterization of a low-carbon insulation foam

Building insulation is currently one of the biggest challenges to reduce energy consumption. Saving energy also means reducing the human impact on Environment. In order to reduce this impact, the manufacturing of the building materials is of importance. Moreover, policies, laws and regulations keep evolving in this direction. Mineral insulations and more precisely mineral insulating foams meet these two objectives. Indeed, in this research, replacing cement by lime and adding Limestone Clay Fines (LCF) enable the production of a mineral foam with comparative thermal and mechanical performances as mineral insulating market products, i.e. respectively under 0.065W/m/K and at least 0.2MPa. Sulfo-Aluminous Cement (SAC) was used to reach both criteria and it shows a key role in the setting. Mixing process choices and more precisely mixing equipment, can also have a significant impact. Indeed, the use of whisk, in place of a blade, produces more quickly a 28% lighter foam. Comparing with other insulating materials, this mineral foam presents one of the lowest CO2 equivalent emissions and also one of the lowest drinking net water consumptions. Additionally, the specificities of this insulation foam pores give to this new material interesting acoustic performances. Indeed, the processed foams are five times better acoustically than aerated concrete. In fact, the internal structure of the mineral foam absorbs up to 80% of low wavelengths.